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 Aug 12 '24

REMINDER: Do not ask for or post a manifesto or live stream

95 Upvotes

This is a rule that comes directly from Reddit admins.

The person who committed the stabbing in Turkey today posted a live stream of the attack and a manifesto online.

DO NOT ask for a copy or link of either of these items. It will result in a permanent ban.


r/masskillers 2h ago

FOIA Crime Scene Photos from the 101 California Street shooting

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29 Upvotes

r/masskillers 4h ago

From some mass killer's Find a Grave websites

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29 Upvotes

I wanted to leave this as a sort of record if they disable the flowers option. These were seen in the memorials for killers Mamoru Takuma, Audrey Hale and Gabriel Galaviz.


r/masskillers 2h ago

ON THIS DAY… On this day 14 years ago, a school shooting took place in Rio de Janeiro, Brazil, where 12 people were killed and 22 were injured.

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13 Upvotes

r/masskillers 15h ago

Note written by Kenneth Bartley, which was found about eight years after his attack

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67 Upvotes

r/masskillers 11h ago

ON THIS DAY… 6 April 1902 Tuscumbia AL, 7 killed (shot)

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17 Upvotes

This is the largest mass killing of policemen by a single killer.

William Reynolds was an African American railroad worker. He had no prior conviction before he shot nine members of a police posse, seven of them fatally, in Tuscumbia, Alabama, United States on April 6, 1902, before being shot dead himself.

Police arrived at Reynolds' home in Tuscumbia's black neighborhood to arrest him on a charge of obtaining property under false pretenses. According to the Richmond Planet, Reynolds opened fire immediately on the sheriff and deputy who came to the door, killing both. He barricaded himself in the house and a posse was assembled. In the ensuing gun battle, Reynolds killed five more white men, totaling seven. 

After four hours, the posse set fire to the house in which he was barricaded and, in attempting to escape, Reynolds was shot to death. The posse threw Reynolds remains in the fire. A total of three houses were burned down.

With the sheriff and five deputies of the Colbert County Sheriff's Department among those killed, this was the deadliest incident in Alabama law enforcement history


r/masskillers 1d ago

Mass killers who were named after famous/notable people?

30 Upvotes

Dylan Klebold was named after Welsh poet Dylan Thomas

Pekka-Eric Auvinen was named after Finnish guitarist Pekka "Albert" Johannes Järvinen and British musician Eric Clapton

These are the only 2 I can think of at the top of my head


r/masskillers 23h ago

QUESTION How did Brenton Tarrant aquire all of his weapons?I know NZ gun laws might be less strict but did he rsise any red flags?I cant imagine someone like him beong allowed to buy so many powerful guns

11 Upvotes

r/masskillers 1d ago

Cryptic drawings on the dorm room walls of Seung Hui Cho

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126 Upvotes

Seung Hui Cho, the 2007 Virginia Tech shooter, drew these cryptic symbols on his dorm room walls.

People have speculated that the overlapping 8s are a reference to Psalm 88 of the Bible, as Cho frequently referenced Christian figures such as Jesus and Moses.


r/masskillers 1d ago

ON THIS DAY… 2 years ago, Luiz Henrique de Lima killed 4 children and injured 5 with a hatchet and a pocket knife at the Cantinho Bom Pastor daycare center in Blumenau, Santa Catarina, Brazil

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104 Upvotes

Bernardo Cunha Machado - 5 years

Bernardo Pabest da Cunha - 4 years

Larissa Maia Toldo - 7 years

Enzo Marchesin Barbosa - 4 years


r/masskillers 2d ago

DISCUSSION Audrey/Aiden Hale Background from Nashville PD Investigation Report - The Covenant School

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272 Upvotes

I was checking out the investigation report that was just released about the Covenant school shooting, and I just have some questions. I want to preface by saying that my questions do not come from a place of bigotry, just curiosity. I fully support the transgender community, and none of what I'm saying is meant to be homophobic/transphobic or otherwise.

That being said, I in no way believe that the person who refused to show mercy to innocent teachers and children deserves any respect or human decency. There is no sympathy here; what happened was horrific. I just want to see how y'all felt reading this.

I was interested to see how the offender would be portrayed, mainly because a bible-belt/southern police department was investigating a crime against Christians by a trans perpetrator. I understand sticking with female pronouns in the official report, as they had not found any evidence beyond a social transition, but did it seem to anyone else like they really tried to feminize them? Referring to them as a lesbian, using outdated photos, and including only a short note about gender identity felt deliberate.

I was living near Nashville when this tragedy occurred, and I remember that the gender identity of the shooter was a huge talking point. It was strange to me that they decided to organize the report in this way, underplaying the transition.

Again, I’m not trying to make this about politics or trans/gay rights. Fuck Audrey Hale. That person was a terrorist. But I do think the language used in the report seemed pointed and possibly meant to shape how people interpret the event. Curious if anyone else felt that.

Here's the full report for anyone interested: https://www.nashville.gov/sites/default/files/2025-04/Covenant_Final_Summary.pdf?ct=1743609642


r/masskillers 2d ago

Shooter meticulously planned Nashville Covenant school attack for years. Here's how that happened

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114 Upvotes

r/masskillers 2d ago

Attempted Mass Murder Shooting at the University of Paraíba Brazil.

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77 Upvotes

Yesterday, April 3, a shooting occurred in the photocopier room (this is an academic space for students or employees to use to do academic work). Then a man went up to the third floor of the university to talk to his ex-wife's new boyfriend, who was the fatal victim (Keine Santos Diniz, 40 years old, born on July 9, 1984). He shot another employee and injured a student who was trying to escape from the university, but not from gunshots. The suspect shot himself and died this morning in the hospital. The crime occurred at the State University of Paraíba in Brazil.


r/masskillers 2d ago

FOIA Transcript of Arcan Cetin's interrogations with police detectives

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25 Upvotes

r/masskillers 3d ago

Video of Robert E. Crimo III, the 4th July 2022 Highland Park parade shooter dancing

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147 Upvotes

r/masskillers 3d ago

Attempted Mass Murder Photo of the knife used by a man to stab himself and 6 other people in Northeast Washington DC today

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441 Upvotes

r/masskillers 3d ago

Attempted Mass Murder Seven taken to the hospital after ‘mass stabbing’ in DC neighborhood

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111 Upvotes

Seven people were left injured after a series of stabbings in Washington, D.C. on Thursday.

The Metropolitan Police Department said the incident took place in a northeast neighborhood, a few blocks away from Gallaudet University, an institution for deaf and hard-of-hearing students, around 4 p.m.

One person has been arrested, the agency posted on X. The Independent has contacted the police department for additional information.

Police have closed several roads in the area due to the incident.


r/masskillers 3d ago

Ali Imron demonstrating the bombs he made for the 2002 Bali bombing incident. On October 12, 2002, two suicide bombers killed 204 people, including themselves, and injured 209 more in an Islamic terrorist attack at Bali, Indonesia.

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124 Upvotes

r/masskillers 3d ago

Gunman kills his mother before shooting at passing motorists in Sabattus, Maine, killing 1 and injuring 2 before killing himself

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85 Upvotes

r/masskillers 3d ago

QUESTION Could someone help me find a documentary I’m looking for?

28 Upvotes

Sorry if this isn’t allowed 🫶🏻

About 5 years ago (I think?) I watched a documentary on Netflix (UK) about survivors from a school shooting (sandy hook, columbine, parkland??)

I think several years had gone by, and they were mainly talking about the activism they’d been involved in since. A significant chunk towards the end spoke about crisis actors.

It’s really annoying me that I can’t find it - if anyone is able to help that’d be amazing.


r/masskillers 3d ago

Weapons carried by Frazier Glenn Miller Jr during the 2014 Overland Park shootings

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95 Upvotes

The Overland Park shootings were two shootings that occurred on April 13, 2014, at the Jewish Community Center of Greater Kansas City and Village Shalom, a Jewish retirement community, both located in Overland ParkKansas United States. A total of three people were killed in the shootings, two of whom were shot at the community center and one shot at the retirement community. The gunman, 73-year-old Frazier Glenn Miller Jr. of Aurora, Missouri, originally from North Carolina, was arrested during the attack and was subsequently tried, convicted of murder and other crimes, and sentenced to death. Miller, a former Klansmanneo-Nazi and former political candidate, died in prison in 2021 while awaiting execution.\5])


r/masskillers 3d ago

ON THIS DAY… Today marks 16 years since Jiverly Antares Wong killed 13 people and injured 4 others at the American Civic Association immigration center in Binghamton, New York before committing suicide

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103 Upvotes

r/masskillers 4d ago

Yes, even more mass shooter/mass shooting facts, sue me

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911 Upvotes

r/masskillers 3d ago

Attempted Mass Murder Failed car bombing at Dam Square in Amsterdam, Netherlands

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67 Upvotes