Three people were found dead late Sunday in a home in Hatfield Borough after what the Montgomery County District Attorney's Office called an apparent double homicide and suicide.

A 48-year-old woman and her 28-year-old son were found shot to death. Also discovered was the body of Paul Marshall, 48, dead of a self-inflicted gunshot wound. The woman and other man were not identified by officials.

"This is a quiet neighborhood. It's not something that you would expect," said Lynne Barnes, 66, who has lived in the area since 1973 and whose house is down the street from where the victims were found, at 138 Diamond St.

Hatfield Township police responded to the house about 11:34 p.m. Sunday after a report of a shooting. Marshall's body was found in possession of a semi-automatic rifle, and shell casings and other ballistic evidence was found, officials said.

An autopsy Monday ruled Marshall's death a suicide.

The TV station 6ABC reported that Montgomery County First Assistant District Attorney Kevin Steele called the case "domestic-related." It reported that neighbors said Marshall was engaged to the female victim and that they lived in the residence with the woman's son as well as Marshall's 27-year-old daughter and 4-year-old grandchild.

Property records indicate Marshall owned the house.

Barnes said she did not know the people who lived in the house, but had seen a young girl playing in the front yard many times. When she saw police outside early Monday, her first thought was of the child.

"I said, 'Oh, my Lord. I hope the little girl is all right,' " she said.

Police reported that a 27-year-old female and a 4-year-old child were both in the house when the shootings occurred but were unharmed.

Two BMWs sat in the driveway Monday morning as news vans lined the street. The home, a split-level, was decorated with Christmas lights that were still shining.

The investigation is ongoing.