TOBYHANNA, Pa. (AP) — A state police fire marshal is investigating an explosion that destroyed a Pennsylvania house that neighbors say had been targeted with swastikas and homophobic graffiti hours earlier.

Investigators could not immediately confirm the graffiti that neighbors told WNEP-TV they saw on the home's garage door on Sunday.

Fire officials say some kind of vapor apparently built up in the house in Coolbaugh Township before the explosion about 3 a.m. Monday.

Nobody was inside. But authorities say the home's owner had been fixing it up.

Coolbaugh Township is about 20 miles (32.2 kilometers) southeast of Scranton, in northeastern Pennsylvania.