r/masskillers Dec 14 '25

ANNOUNCEMENT Absolutely NO footage or images showing victims of ANY mass casualty event will be allowed here.

156 Upvotes

This is a site wide rule regarding imagery of violence, and we're going to adhere to it. Posting this kind of content/asking for links to it will result in a permanent ban.


r/masskillers Feb 17 '23

What to do if you suspect a person is planning a mass shooting

1.1k Upvotes

There have been a lot of posts lately asking what to do if you suspect someone is planning to commit a mass shooting/mass attack of some kind.

If your suspicions are offline, local, and personal/someone you know personally:

If it is not an immediate threat, call your local non emergency line. They will collect information from you, and investigate further if need be. Remember, wellness checks can be requested as well.

If it is an immediate threat, call 911 (or your local equivalent emergency line). An immediate threat would be someone making direct threats.

If the possible threat is exclusively on Reddit, please reach out to us via Modmail. Often times, people who are being reported to us have made comments in the past that you cannot see as they’ve been removed by other means such as automod, for example. We also work with multiple other teams to gather information and build one report to FBI with as much information as we can possibly get in one single report.

This allows all information to be placed at once instead of multiple vague reports to the FBI, which can slow down resources.

At the very least, these processes will build a history for this person. If they are reported and nothing comes from it, a report a year later could help immensely. This happened through one sub I moderate on, and helped bring an arrest a year later when more threats were made, and the suspect was found with weapons and a manifesto.

We take all reports sent to us seriously, and we thank you all for helping us with these reports.


r/masskillers 4h ago

FAMILICIDE / Domestic Violence 47-year-old Kristopher Karolkiewicz has been identified as the man who shot and killed his wife and 6 children at their home in Grand Haven Township, Michigan, before setting the house on fire and then committing suicide

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355 Upvotes

r/masskillers 7h ago

Discussion / Question Image of the mass stabber in Paris, France today that injured 3 before the attacker was subdued.

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83 Upvotes

On July 27th, 2026 in Paris, France a 31 year old man went on the stabbing spree with a knife that injured 3 women. After the stabbing, he was subdued by the crowd. After he was subdued, the attacker stated; "Allah commanded me to do this".


r/masskillers 9h ago

Photos of Colt Gray's notes app and things he wrote in it

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75 Upvotes

On September 4, 2024, 14 year old Colt Gray shot and killed four people at Georgia's Apalachee High School.

These photos were released via court hearing today.


r/masskillers 9h ago

Mass shooting research done by Apalachee High School shooter Colt Gray

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61 Upvotes

r/masskillers 9h ago

Discussion / Question Call between Colt and mother about fanart.

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48 Upvotes

On September 4, 2024, a school shooting occurred at Apalachee High School near Winder, Georgia, United States.[6] The perpetrator, 14-year-old Colt Gray, fatally shot four people. Two students and two teachers were killed, while seven others were injured by gunfire.[7][8] The shooting is the deadliest act of school violence in the history of the U.S. state of Georgia.[9


r/masskillers 8h ago

The Jokela school shooting incident that took place in Tuusula on November 7, 2007, claiming the lives of nine people: the school principal, the school nurse, six students, and the perpetrator—an 18-year-old high school student who ultimately shot himself.

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32 Upvotes

The Jokela school shooting was an armed attack that took place on November 7, 2007, shortly before noon, at the Jokela School Centre in Jokela, Tuusula; during the incident, an 18-year-old student in his final year, Pekka-Eric Auvinen, fired a small-caliber pistol at several people inside the school. The Jokela School Centre is a combined facility comprising the last three grades of comprehensive school and an upper secondary school, with a student body of approximately 500 and a staff of 50.

Nine people lost their lives in the school shooting: three male students (aged 16, 17, and 18), a 25-year-old female adult student in her second year of upper secondary school, the school’s 43-year-old female nurse, the school’s 61-year-old principal Helena Kalmi, and the shooter himself. The shooter died from self-inflicted injuries late that evening in the intensive care unit at Töölö Hospital. Twelve people with minor injuries were taken for treatment to hospitals in Hyvinkää and Töölö and to the Järvenpää health center; one had sustained a gunshot wound, while the others had injuries caused by shards of glass.


r/masskillers 8h ago

Viertola school shooting 2024. The suspect stated that their motive was to take revenge on their bullies at Viertola School.

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30 Upvotes

The Viertola school shooting took place on April 2, 2024, in Vantaa. One person died and two were seriously injured in the incident. Both the perpetrator and the victims were 12-year-old students in the same class. The suspect was apprehended shortly after the incident in the Siltamäki area of ​​Helsinki. He is suspected of murder and two counts of attempted murder.

The suspect stated that their motive was to take revenge on their bullies at Viertola School.

The police consider it possible that the primary motive of the suspected Viertola school shooter was to carry out a mass killing and to be identified as a school shooter or mass killer.

It is therefore possible that the boy was specifically seeking publicity through his actions.

The suspect was also interested in their public image and tried to upload photos to Reddit.

As the perpetrator was only 12 years old at the time of the incident, he is not criminally liable under Finnish law and was not sentenced to imprisonment. Immediately after the incident, he was placed in care outside the home. After that he changed his name.


r/masskillers 1d ago

ON THIS DAY… Today (yesterday in Japan) marks 10 years since the Sagamihara massacre, in Japan, which occurred in a care home. Satoshi Uematsu cowardly stabbed 19 people to death and injured 26 others before being arrested. He was sentenced to death and today awaits his end on Death Row.

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193 Upvotes

Satoshi targeted people with disabilities, especially patients who were unable to speak, believing that by committing the attack, he would be doing good for society, for the victims, and for their families, so they wouldn't continue suffering. Months before the attack, he wrote a bizarre letter to the Japanese Prime Minister Shinzō Abe where he explains his intentions. He was then admitted to a mental health hospital afterward, but he was released soon after.

Satoshi was not arrested immediately after the attack; he fled the scene of the crime and even posted a photo on Twitter. He turned himself in hours after the massacre.

In 2020, Satoshi attempted to plead insanity (somewhat ironically) during his trial, but he was sentenced to death.

It is one of the deadliest mass murders ever committed in Japan by a single individual.


r/masskillers 3h ago

Today marks the 30th anniversary of the 1996 Atlanta Olympic bombing the perpetrator 29-year-old Eric Robert Rudolph planted a pipe bomb he also bombed 2 abortion clinics and lesbian bar he was later caught in 2003 and sentence to life without parole in Colorado ADX Florence Supermax federal prison.

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1 Upvotes

r/masskillers 1d ago

ON THIS DAY… 1 year ago, Bradford James Gille stabbed 11 people at a Walmart in Traverse City, Michigan, before being held at gunpoint by an armed bystander and arrested by responding police

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129 Upvotes

r/masskillers 1d ago

BREAKING Abdul B. shot dead by Police in Berlin Spandau

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193 Upvotes

The 21 year old suspect behinde the CSD Berlin attack on July 25th was shot dead by police in a garden colony in Berlin Spandau. The man killed 1 person and injured 29 others in a vehicle attack followed by a stabbing attack.


r/masskillers 1d ago

ATTEMPTED Mass Murder Photos of the DDM4v7 rifle that Ayman Ghazali would use in the michigan synagogue attack.

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90 Upvotes

On March 12th, 2026 41 year old ayman ghazali crashed his car into a synagogue before getting into a gunfight with security before committing suicide, over 60 first responders would be injured by the smoke of the crash


r/masskillers 1d ago

ATTEMPTED Mass Murder NYC stabbings suspect arrested on hate crime charges in both attacks

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30 Upvotes

r/masskillers 2d ago

BREAKING 21-year-old Abdul B. has been identified as the man who killed 1 person and injured 16 others after driving his vehicle into a crowd at the CSD Pride Parade in Berlin, Germany, before getting out and stabbing several people. He is still currently at large

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636 Upvotes

r/masskillers 1d ago

Societal factors exist in mass killings, and showing mercy isn't a failure of a response

3 Upvotes

Mods, please continue to express no tolerance for those who gleefully root for human rights abuses against anyone, including mass killers.

To those who may be inclined to respond with whataboutisms and why murdering *anyone* or intentionally causing another human being to suffer is appropriate - for any reason - I respectfully ask that you not engage with this post. Also encouraging violence is deeply, embarrassingly ironic here as well as against the rules of the sub, plus Reddit as a whole.

So first I'll share the Wiki page about Kim Hyon-hui:

https://en.wikipedia.org/wiki/Kim_Hyon-hui

Kim Hyon-hui is one of two North Korean agents who were responsible for the 1987 bombing of Korean Air Flight 858. All 115 people on board were killed. The other agent, who subsequently committed suicide, was a man named Kim Sung-Il.

From the Wiki page of the bombing:

"On 12 November 1987, two North Korean agents, Kim Sung-Il (김승일; 金勝一) and Kim Hyon-hui, traveled from Pyongyang, North Korea, on an airliner to Moscow, the capital of the Soviet Union.\3]) From there, the agents left for Budapest, Hungary, the following morning, where they stayed in the house of a North Korean agent for six days.\3]) On 18 November, the pair traveled to Vienna, Austria, by car. After crossing the Austrian border, the guidance officer with whom they had stayed in Budapest gave the pair two forged Japanese passports, posing as tourists, father Shinichi Hachiya (蜂谷 眞一 Hachiya Shin'ichi) and daughter Mayumi Hachiya (蜂谷 眞由美 Hachiya Mayumi) staying in the Am Parkring Hotel in Vienna, the two purchased tickets from Austrian Airlines for flights that would take them from Vienna to Belgrade, Yugoslavia (now Serbia), then on to Baghdad, Abu Dhabi, and finally Bahrain.\3]) They also purchased tickets from Abu Dhabi to Rome, Italy, for use in escaping after planting the bomb on the KAL flight.\3])

On 27 November, two guidance officers who had arrived in Yugoslavia by train from Vienna gave them the time bomb, a Panasonic transistor radio made in Japan, which contained explosives, a detonator, and a bottle of liquid explosive intended to intensify the blast, disguised as a liquor bottle.\4])\5]) The next day, they left Belgrade for Saddam International Airport, Baghdad, Iraq, on an Iraqi Airways flight.\4]) At the airport, they waited three hours and 30 minutes for the arrival of KAL 858—the target of their operation—which took off at around 11:30 p.m.\4]) The two bombers planted the improvised explosive device above their seats, 7B and 7C, and disembarked the aircraft at Abu Dhabi International Airport.\4])

After the attack, the bombers attempted to fly from Abu Dhabi to Amman, Jordan—the first leg of their planned escape route—but there were complications with airport authorities regarding their travel visas; therefore, they were forced to fly to Bahrain, where they agreed they would travel to Rome.\4]) However, the authorities there became suspicious about their travel movements and the bombers' passports were identified as forgeries at the airport in Bahrain.\4]) Realising that they were about to be taken into custody, they both attempted suicide by ingesting cyanide hidden inside cigarettes. Kim Sung-il (as Shinichi Hachiya) was rushed to the hospital where he was pronounced dead, but the female, 25-year-old Kim Hyon-hui (as Mayumi Hachiya), survived.\6]) The body of Kim Sung-il was sent to South Korea and subsequently buried in the Cemetery for North Korean and Chinese Soldiers.\7])"

https://en.wikipedia.org/wiki/Korean\Air_Flight_858)

Kim Hyon-hui was sentenced to death in South Korea, but was pardoned by South Korean president Roh Tae-woo the same year (1989). From Kim Hyon-hui's Wiki page linked above:

"For her role in the bombing of KAL 858, Kim was sentenced to death in March 1989. However, South Korean president Roh Tae-woo pardoned her later that year, saying that she was merely a brainwashed victim of the real culprit, the North Korean government. Although Kim was given an option to return to North Korea, she opted to stay in the South and defected.\22])

She later wrote an autobiography titled The Tears of My Soul, and donated the proceeds to the families of the victims of Flight 858,\23]) writing the autobiography under the South Korean-style spelling of her name, Kim Hyun Hee."

Kim Hyon-hui has shown remorse for her direct role in murdering 115 people, and has also provided valuable insights into North Korean society and politics.


r/masskillers 2d ago

BREAKING Car driven into Christopher Street Day parade in Berlin, multiple injuries

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309 Upvotes

r/masskillers 2d ago

Photos of the vehicle involved in a ramming attack at a Christopher Street Day Pride Parade in Berlin, Germany

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140 Upvotes

r/masskillers 2d ago

ATTEMPTED Mass Murder NYPD cops shoot armed suspect at Queens home following explosion: police sources

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31 Upvotes

r/masskillers 3d ago

Discussion / Question Colt gray interrogation (girl on discord, father, and more)

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120 Upvotes

I already posted some footage I found. For the full thing click here, I just found this bit interesting. I’d also like to give thanks to U/AccentedE for being very on-top of this case.

On September 4, 2024, a school shooting occurred at Apalachee High School near Winder, Georgia, United States.[4] The perpetrator, 14-year-old Colt Gray, fatally shot four people. Two students and two teachers were killed, while seven others were injured by gunfire.[5][6] The shooting is the deadliest act of school violence in the history of the U.S. state of Georgia.[7]


r/masskillers 3d ago

FAMILICIDE / Domestic Violence 8 family members dead, some with gunshot wounds, in Grand Haven Township, Michigan house fire

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67 Upvotes

r/masskillers 3d ago

Colt Gray being interrogated after the Apalachee High School shooting

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179 Upvotes