Lakewood police arrested a teenager Saturday night in connection with a bomb threat made against Green Mountain High School, the department said in a press release Sunday afternoon.

The teenager made the threats, which included telling students not to go to school Monday, via an anonymous Google doc that was then posted to an Instagram account that Green Mountain students use to “vent,” Lakewood Police spokesman John Romero said. Once the threat was posted, police received several Safe2Tell reports about the threats.

Romero confirmed that the teenager is a Green Mountain student, though he declined to provide additional details about them because detectives are still trying to figure out if the teenager acted alone.