A strong fire quickly burned a home to the ground in Milford early Saturday, leaving a family of six homeless. The fire, at 13 Domenick St., was reported about 4 a.m. after neighbors heard windows breaking, said Lieutenant Patrick Salmon of the Milford Fire Department. The family of four children and two adults that lived in the building was not home, Salmon said. Within 10 minutes, the dwelling collapsed. Noticing signs of impending collapse, firefighters had retreated away from the building, Salmon said. “It was so far gone when we got there, the priority was to protect the surrounding structures, and the firefighters did that well,” Salmon said. The cause of the fire, which reached three alarms and drew mutual aid from seven communities, is under investigation.