Two teens were hurt in an explosion at a North Seattle home on Sunday.
The explosion shattered windows in living room and kitchen of the home at 2212 N 106 St., blew open the back door and propelled debris out into the back yard, police said.
Police say the father of one of the boys, who is also the uncle to the other, was in the house when the explosion occurred but was in another room asleep at the time.
He told police his son had been working on a school science project involving model rocketry. He said the boys were apparently trying to start a fire in the fireplace and may have used some of the rocket fuel they had mixed up as a means of getting the fire going, or they were testing the mixture.
Police said a preliminary investigation found that the living room was being used as a workshop. Police found several completed homemade fireworks bottle rockets, small aerial display mortars, and a skyrocket.
Also found were assorted chemical powders for mixing up pyrotechnic powders.
The completed items were seized for destruction, police say.