TAMPA, Fla. (AP) — A California teenager pleaded guilty Wednesday in a case involving the swatting of a Florida mosque among other institutions and individuals, federal prosecutors said.

Alan W. Filion, 18, of Lancaster, California, entered the plea to four counts of making interstate threats to injure the person of another, the U.S. Attorney’s Office for the Middle District of Florida said in a news release. He faces up to five years in prison on each count. A sentencing date has not yet been set.

Swatting is the practice of making a prank call to emergency services in an attempt to bring about the dispatch of a large number of armed police officers to a particular address. Bomb threats go back decades in the U.S., but swatting has become especially popular in recent years as people and groups target celebrities and politicians.

“For well over a year, Alan Filion targeted religious institutions, schools, government officials, and other innocent victims with hundreds of false threats of imminent mass shootings, bombings and other violent crimes. He caused profound fear and chaos and will now face the consequences of his actions,” Deputy Attorney General Lisa Monaco said in a news release.

FBI Deputy Director Paul Abbate said Filion intended to cause as much harm as possible and tried to profit from the activity by offering swatting-for-a-fee services.

“Swatting poses severe danger to first responders and victims, wastes significant time and resources, and creates fear in communities. The FBI will continue to work with partners to aggressively investigate and hold accountable anyone who engages in these activities,” Abbate said.

The U.S. Attorney’s Office said Filion made more than 375 swatting and threat calls from August 2022 to January 2024. Those calls included ones in which he claimed to have planted bombs in targeted locations or threatened to detonate bombs and/or conduct mass shootings at those locations, prosecutors said.

He targeted religious institutions, high schools, colleges and universities, government officials and people across the United States. Filion was 16 at the time he placed the majority of the calls.

Filion also pleaded guilty to making three other threatening calls, including an October 2022 call to a public high school in the Western District of Washington, in which he threatened to commit a mass shooting and claimed to have planted bombs throughout the school.

He also pleaded guilty to a May 2023 call to a historically black college and university in the Northern District of Florida, in which he claimed to have placed bombs in the walls and ceilings of campus housing that would detonate in about an hour. Another incident was a July 2023 call to a local police-department dispatch number in the Western District of Texas, in which he falsely identified himself as a senior federal law enforcement officer, provided the officer’s residential address to the dispatcher, claimed to have killed the federal officer’s mother, and threatened to kill any responding police officers.