Police arrested a 20-year-old Lawrence man, Dakota Jackson Kunkle, Sunday morning on suspicion of criminal use of explosives at an apartment in the 700 block of West 25th Street.

Douglas County prosecutors on Monday filed two counts of criminal use of an explosive against Kunkle. In one of the counts, prosecutors accuse him of placing a public safety officer “at risk to defuse” it. The second count is related to an alleged incident on July 4, 2011, according to the charges.

Kim Murphree, a Lawrence police spokeswoman, said officers were called about 11:30 p.m. Saturday to assist firefighters with items found at the scene during a fire call. Other officers and firefighters had been sent to the same residence an hour earlier to a report of gunfire. Police later determined the sounds involved firework ignition powder. According to court records, the Leavenworth Fire Department responded, and the agency has a bomb squad.

“An investigation determined the occupants of the residence had been making homemade explosives with at least one possible detonation inside the residence,” Murphree said.

A judge Monday set Kunkle’s bond at $20,000 and scheduled his next hearing for Wednesday.