This has just been reported a few hours ago, no details have been released besides what is in this from a link to the report from Reuters:
Five members of a family, including three children, were found shot dead at their southern Maine home on Sunday, with a gun located near one of the bodies and no outside involvement suspected, a police spokesman said.
The five, a father and mother in their 30s and three children believed to be 4, 7 and 12, were discovered on Sunday afternoon in three rooms of their second-floor apartment in Saco, about 17 miles (27 km) southwest of Portland, state police spokesman Stephen McCausland said.
Just another day in America's gun culture. Five more bodies we can stack up upon the altar of the second Amendment.