YouTube shooting: It is rare that women are the ones pulling the trigger in active shooting incidents

Show Caption Hide Caption Reports of a shooting at YouTube San Bruno HQ Police in Northern California are responding to reports of a shooting at the headquarters of YouTube in the city of San Bruno. (April 3)

As YouTube's bright headquarters in Northern California became the epicenter of the latest shooting in the U.S. on Tuesday, five words from police at an afternoon news conference stood out: The female suspect is dead.

It is rare for women to pull the trigger in workplace and mass shootings.

Of 28 mass attacks analyzed by the Secret Service in 2017, all 28 involved male attackers, the service said in a recent report.

In Tuesday's incident, the female suspect died in an apparent suicide after opening fire and wounding three people at the YouTube facility in San Bruno, Calif., about 11 miles south of San Francisco, police said. Her motive was still being investigated.

One of the most recent cases of a female shooter was that of Tashfeen Malik, 27, the wife of Syed Farook, 28. Malik helped her husband carry out a deadly rampage in San Bernardino, Calif., on Dec. 2, 2015, when the couple burst into a meeting room at the Inland Regional Center, an agency that provides services for the developmentally disabled, and gunned down 14 people.

Farook was a U.S.-born citizen of Pakistani descent and worked at the health department; Malik was a Pakistani-born lawful permanent resident of the U.S. The couple, who lived in Redlands, fled after the assault and later died in a shootout with police.

A special report by USA TODAY documents how rare female shooters are: Women are suspects in just 6% of mass killings in the U.S., according to "Behind the Bloodshed," a USA TODAY analysis. The average age of a female mass killing suspect is 33; the youngest is 18, according to the report. That compares to men with an average age of 31.

More: 64% of assailants in mass attacks suffered from symptoms of mental illness, Secret Service report finds

More: Female suspect dead, 4 injured after shooting at YouTube headquarters in California

In another analysis, only six of 160 shootings from 2000 to 2013 that fit the active shooter definition were carried out by females, according to a 2014 study by the FBI and Texas State University. Law enforcement officials use the term "active shooter" to describe an individual actively engaged in killing or attempting to kill people in a confined and populated area.

Those included:

• Yvonne Hiller, 43, who opened fire on her co-workers at a Kraft Foods Factory in Philadelphia on September 2010 shortly after being suspended from her job. Hiller had been escorted from the building but returned. Two people were killed and one was wounded. Hiller exchanged gunfire with police but was eventually apprehended.

• Biology professor Amy Bishop Anderson, 44, who killed three and wounded three others after opening fire in February 2010 at a department meeting at the University of Alabama in Huntsville. Anderson, who had been denied tenure at the university almost a year earlier, did not open fire until 30 minutes into the meeting. She surrendered to responding officers.

• Latina Williams, 23, who killed two fellow students in a classroom at Louisiana Technical College in Baton Rouge in February 2008. She fired six rounds, then reloaded and committed suicide before police arrived.

• Former postal worker Jennifer San Marco, 44, who opened fire in January 2006 at the Santa Barbara U.S. Postal Processing and Distribution Center in Goleta, Calif. She killed six before turning the gun on herself. San Marco, who left the postal service three years before the incident, suffered from mental illness.

• In April 2001, Cathline Repunte, 36, opened fire at the Laidlaw Transit Services maintenance yard in San Jose, Calif., killing a fellow school bus driver. At her trial, psychiatrists said Repunte suffered from paranoid schizophrenia.

Contributing: Kevin Johnson