Workplace Violence: 15 of the Most Terrifying Murders on the Job

It’s not unusual to get angry at work from time to time. However, some people have trouble learning how to handle that anger. So the anger turns into rage and sometimes results in murder. Workplace homicides rose by 2% to 417 cases in 2015, with shootings rising by 15%, according to the Bureau of Labor Statistics.

Workplace violence accounts for 17.8% of all simple assaults and 12.9% of all aggravated assaults. In addition, workplace violence costs American businesses anywhere from $6 billion to $36 billion each year, reported TAL Global. Here are 15 of the most terrifying homicides on the job.

1. Raymond Clark III

Yale muder

The killer received a 44-year sentence. | Spencer Platt/Getty Images

  • Year tragedy took place: 2009
  • Number of people killed: 1

Annie Le worked at the Yale Animal Research Center, where she conducted medical experiments, according to Yale Alumni Magazine. The 24-year-old suddenly went missing days before her wedding. Her body was later found behind one of the walls in the research lab Sept. 13, 2009, the day of her wedding. Strangulation was the cause of death, the New Haven Register reported. Her co-worker Raymond Clark III received a 44-year prison sentence for her murder.

Next: This mass killing took place the day after Christmas.

2. Michael McDermott

Michael McDermott shooting

Wage garnishment upset him. | Victoria Arocho/Pool/Getty Images

  • Year tragedy took place: 2000
  • Number of people killed: 7

Michael McDermott worked as a software engineer for Edgewater Technology in Wakefield, Massachusetts. The day after Christmas, he came to work with an AK-47 assault rifle, a shotgun, and a semiautomatic pistol. McDermott then proceeded to shoot and kill seven of his co-workers. Time magazine reported McDermott targeted workers in the human resources and accounting departments after he was about to have his wages garnished to pay overdue taxes to the IRS. He allegedly asked for a cash advance the week before Christmas but was denied. McDermott was sentenced to seven consecutive life sentences without parole.

Next: This killer went over the edge after losing his job. 

3. Andrew John Engeldinger

woman with gun

He was angry after the company fired him. | Kevork Djansezian/Getty Images

  • Year tragedy took place: 2012
  • Number of people killed: 5

After working at Accent Signage Systems factory in Minneapolis for 12 years, Andrew John Engeldinger was told his services were no longer needed, reported the Star-Tribune. Angered by the news, Engeldinger retrieved a 9mm Glock handgun and killed five people and injured three. Among the dead was the founder of the company, Reuven Rahamim. Engeldinger then shot himself in the head.

Next: This killer had help from his wife.

4. Syed Rizwan Farook and Tashfeen Malik

Mass Shooting In San Bernardino Leaves At Least 14 Dead

The couple killed 14 people. | Sean M. Haffey/Getty Images

  • Year tragedy took place: 2015
  • Number of people killed: 14

Syed Rizwan Farook worked as an environmental health specialist at the San Bernardino County health department, which was preparing to host a holiday party at the Inland Regional Center, according to CNN. Farook and his wife, Tashfeen Malik, opened fire during a company training session, killing 14 people and wounding 21. Farook and Malik were later killed during a shootout with police. Authorities later found the couple had a bomb lab in their townhouse as well as thousands of rounds of ammunition.

Next: This killer took out her anger on her colleagues at the post office.

5. Jennifer San Marco

Jennifer San Marco post office shooting

The woman had a history of erratic behavior. | David McNew/Getty Images

  • Year tragedy took place: 2006
  • Number of people killed: 7

Jennifer San Marco worked as a postal worker at the Santa Barbara Processing and Distribution Center. San Marco was said to have a history of erratic behavior and was escorted from her job in 2003 after screaming and making racist comments, reported CBS news. Three years later, San Marco decided to return to her former workplace one last time. After shooting and killing her neighbor, San Marco went to the postal facility and shot six of her co-workers before shooting herself.

Next: This killer thought others were out to destroy him.

6. Mark Orrin Barton

Atlanta, Georgia

The Atlanta man had a history of physical and sexual violence. | iStock/Getty Images

  • Year tragedy took place: 1999
  • Number of people killed: 12

Mark Orrin Barton killed nine people in the brokerage houses where he traded, The New York Times reported. Barton then shot and killed himself in his van. Police later found a letter written by Barton saying he planned to live long enough to kill ”the people that greedily sought my destruction.” He also confessed in the letter he had bludgeoned his wife and two children to death with a hammer. It was revealed by the president of Momentum Securities, where Barton killed four people, that prior to the massacre Barton lost approximately $105,000 during 15 days of securities day trading.

Next: Being late to work helped save this employee’s life.

7. Salvador Tapia

Salvador Tapia shooting Windy City Core Supply

He returned for revenge and killed two-thirds of the company’s employees. | Tim Boyle/Getty Images

  • Year tragedy took place: 2003
  • Number of people killed: 6

Six months after being fired from Windy City Core Supply, Salvador Tapia returned to his former job for revenge. Tapia was let go due to repeated lateness and poor work performance. He shot and killed six of the company’s nine employees. The company’s president, Robert Bruggeman, was late to work and survived, reported The New York Times. Tapia was later shot and killed by police.

Next: This killer felt he was being mistreated.

8. Patrick Henry Sherrill

Green mailbox with red flag

The mail carrier had received complaints about his performance. | kirill4mula/iStock/Getty Images Plus

  • Year tragedy took place: 1986
  • Number of people killed: 14

Patrick Henry Sherrill worked part time as a mail carrier for the post office in Edmond, Oklahoma, according to Time. During his 16 months on the job, he received several complaints for misdirected mail and poor performance. After being reprimanded by two of his managers, Sherrill told a steward at his union he was being mistreated. The following day, he shot and killed 14 postal workers, including one of the managers who reprimanded him. Six co-workers were wounded. Sherrill died after shooting himself in the head.

Next: This killer was angry about his company’s decision.

9. Joseph Wesbecker

rows of guns in the UK

His company had put him on disability leave for mental illness. | Scott Barbour/Getty Images

  • Year tragedy took place: 1989
  • Number of people killed: 8

Joseph Wesbecker worked at a printing plant in Louisville, Kentucky, according to The New York Times. Angered after his company put him on permanent disability leave because of mental health issues, Wesbecker shot and killed eight of his co-workers. The San Diego Union-Tribune reported he was looking to kill the company’s executives but couldn’t locate them, so he decided to shoot indiscriminately. Wesbecker then turned the gun on himself.

Next: This killer made multiple threats before acting out.

10. Douglas P. Williams

Gunman Kills Six At Lockheed Martin Factory In Mississippi

He had made concerning comments before. | Marianne Todd/Getty Images

  • Year tragedy took place: 2003
  • Number of people killed: 5

Douglas Williams was an assembly-line worker for Lockheed Martin. Former co-workers said Williams openly made comments about shooting people. One day, he walked out of an ethics and sensitivity training session at his job. He later returned with a semiautomatic rifle and a shotgun, shooting and killing five co-workers before shooting himself, reported The New York Times.

Next: This killer took his personal problems to work.

11. Cedric Larry Ford

Excel Industries Shooting

The painter managed to injure 14 people. | Kyle Rivas/Getty Images

  • Year tragedy took place: 2016
  • Number of people killed: 3

Cedric Larry Ford worked for Excel Industries as a painter. Using an assault rifle, Ford randomly shot at his co-workers, reported NBC News. He killed three and injured 14. About 90 minutes before Ford carried out the killings, he was served with a restraining order at his job. Authorities believe this might have triggered the shooting. The protection of abuse order was filed by his girlfriend. Ford was later shot and killed by a police officer.

Next: This killer’s obsession with a co-worker drove him to the edge.

12. Richard Wade Farley

a display of assault rifles on a wood wall beneath an American flag

He had three different guns with him at the time. | Jim Watson/AFP/Getty Images

  • Year tragedy took place: 1988
  • Number of people killed: 7

Richard Wade Farley worked as a software engineer for ESL Incorporated in Sunnyvale, California. He was fired in 1986 for poor work performance and for the alleged sexual harassment of co-worker Laura Black. Two years later, he returned to his former employer to get revenge. The Washington Post reported he armed himself with semiautomatic pistols, a high-powered rifle, and a 12-gauge shotgun. He used the shotgun to kill seven of his co-workers and injure four. During a five-hour conversation with police, Farley spoke about the loss of his home, his unrequited love, and his rising debt. Farley, who later gave himself up to police, received a death sentence.

Next: This killer couldn’t handle losing his job.

13. Omar Thornton

Omar Thornton beer distributor shooting

He turned violent after being asked to resign. | Douglas Healey/Getty Images

  • Year tragedy took place: 2010
  • Number of people killed: 8

Omar Thornton worked as a driver for a Connecticut beer distributor, ABC News reported. However, he was asked to resign from his position after surveillance video revealed he was stealing beer from the warehouse. After the meeting with his managers, Thornton took out his handgun, shooting and killing eight of his co-workers and injuring two. He then turned the gun on himself.

Next: This killer threatened his co-worker before acting out.

14. Jeffrey Johnson

Jeffrey Johnson shooting NYC

The man blamed his co-worker for his financial problems. | Mario Tama/Getty Images

  • Year tragedy took place: 2012
  • Number of people killed: 1

Jeffrey Johnson worked as an accessories designer at Hazan Imports in New York City, according to NBC. Johnson had been feuding with one of his co-workers, Steven Ercolino. The two had even filed police reports against each other. According to one of the police reports, Johnson allegedly threatened to kill Ercolino. The New York Post reported after Johnson was laid off, he fell on hard times and faced eviction. One year after the layoff, Johnson made good on that threat and shot Ercolino five times in front of their office near the Empire State Building. A construction worker tipped off police, and Johnson was shot dead as he tried to get away. The gunfire exchange injured nine bystanders. A police source told the New York Post Johnson blamed Ercolino for his financial woes and finally went over the edge after facing the loss of his home.

Next: These co-workers had a longstanding feud.

15. Sandra Waller

Burlington Coat Factory

The Burlington employee shot and killed her co-worker. | jetcityimage/iStock/Getty Images

  • Year tragedy took place: 2017
  • Number of people killed: 1

Sandra Waller worked at a Burlington store in Taylor, Michigan, with Lorraine Faison. After the two women got into a heated argument, Waller shot Faison in the chest. It is alleged the fight occurred over how to discount merchandise. The News-Herald reported the women had argued in the past and were involved in a longstanding feud. Waller was later charged with first-degree murder.

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