A California teenager pleaded guilty Wednesday in one case involving the smashing of a mosque in Florida among other institutions and individuals, federal prosecutors said.

Alan W. Filion, 18, of Lancaster, California, pleaded guilty to four counts of interstate threatening to injure the person of another person, 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 charge. A sentencing date has not yet been set.

Swatting is the practice of making a hoax call to the emergency services in an attempt to cause a large number of armed police officers to be sent to a particular address. Bomb threats date back decades in the US, but swatting has become especially popular in recent years as people and groups target celebrities and politicians.

“For more than 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 deep fear and chaos and will now face the consequences of his actions,” Assistant Attorney General Lisa Monaco said in a press 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 services for a fee.

“Swatting poses a serious 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 threatening and threatening calls from August 2022 to January 2024. Those calls included some in which he claimed to plant bombs at targeted locations or threatened to detonate bombs and/ or that he will conduct mass shootings in 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 most of the calls.

Filion also pleaded guilty to 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 placed bombs throughout 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, claiming he had killed the federal officer’s mother and threatening to kill all responding police officers.