PORTLAND, Ore. -- A 19-year-old Portland man was arrested at an Oregon State University campus concert on Sunday after police found illegal fireworks in his backpack.

Courtesy: Benton County

Nicholas Dyer, 19

Nicholas Dyer, a university sophomore, was caught with fireworks and what police called an “explosive device” at the Flat Tail Festival after police questioned him for allegedly urinating in bushes near the concert.

During the questioning, Corvallis police found the fireworks and what they called a small “improvised explosive device” in Dyer’s backpack.

An Oregon State Police officer told the Corvallis Gazette Times that Dyer had taken a 20-ounce water bottle and filled it with firecracker powder.

An OSP bomb squad was called in from Salem to defuse the “explosive.”

Dyer was charged with unlawful possession and manufacturing of a destructive device, two Class C felonies. He was released from Benton County Jail later Sunday.

Dyer’s mother said her son is a “good kid” who made a mistake and is embarrassed by his “poor judgment.”