PORTLAND, Ore. (AP) — An Oregon man arrested last week after an explosion in his SUV now faces federal charges.

Authorities said Thursday that Jason Schaefer of Portland is accused of assault on a federal officer and using an explosive in the course of committing a felony.

An FBI agent wrote in a newly unsealed affidavit that Schaefer yelled to police who pulled him over that everyone was going to die, and then triggered the blast by holding a lighter to a packet.

The 26-year-old Schaefer lost several fingers in the explosion. The affidavit says a detective working with the Joint Terrorism Task Force suffered ringing in his ears, and was hit with glass and the flesh from Schaefer's mangled left hand.

Authorities had been monitoring Schaefer since September, concerned that the felon on probation bought explosives.

Court records do not yet list an attorney to speak on Schaefer's behalf.