A new report released by the FBI says there were 30 active-shooter situations in 2017, more than any year previously recorded. The bureau defines an active-shooter situation as one or more individuals “actively engaged in killing or attempting to kill people in a populated area” with the use of one or more firearms.

The report cited 50 active-shooter incidents in 2016 and 2017. They left 221 people dead and 722 wounded. All of the shooters were male and each incident was a “single-shooter event.” Three events made those numbers skyrocket: the 2017 Las Vegas shooting (58 killed, 489 wounded), the 2016 Orlando nightclub shooting (49 killed, 53 wounded), and the 2017 church shooting in Sutherland, Texas (26 killed, 20 wounded).

The FBI said the report was undertaken “to provide clarity” to federal, state and campus law enforcement, educators and the general public as they “seek to neutralize threats” and save lives during active-shooter incidents.

The report said officers exchanged gunfire with shooters in 14 incidents. Thirteen officers were killed in six incidents and 20 were injured in eight events. It said the most came from the 2016 shooting at a protest in Dallas, Texas, in which five officers were killed and nine injured.

In 10 incidents, citizens confronted the shooter. In eight of those incidents, one or more citizens successfully ended the shooting. In four of the incidents, citizens possessed valid firearms permits and successfully ended the incident. “Their selfless actions likely saved many lives,” the report said.

Former FBI Agent James Gagliano said he wasn’t surprised by the report’s findings. He said the rise of violence could be blamed on a number of factors, including video games, copycats and accessibility to guns. “Part of it is these individuals who see one gunman on the news and the think, ‘Wow, if they did this, I can do it, too,'” Gagliano said. “It’s a vicious circle and for the most part after these incidents, nothing changes. We all retreat to our corners and bicker.”