Police are investigating the execution-style shooting deaths of a woman in a wheelchair and her 42-year-old daughter in their Northeast Philadelphia rowhouse.

Homicide detectives were questioning a 39-year-old man, described as the younger woman's boyfriend, who greeted officers at the door of the house on the 1200 block of Greeby Street in Oxford Circle when they responded to a call about a shooting shortly after 11 p.m. Monday, Capt. John Ryan, the homicide squad's commander, said at a Tuesday news conference.

The boyfriend, who also lived in the home, is considered a possible suspect but was not charged as of late Tuesday afternoon.

After the boyfriend let police in, police found the victims — a 66-year-old woman, identified as Adeline Hill, in a wheelchair with a bullet wound to the head on the ground floor, and her daughter, identified as Renee Cosom, who had been shot in the face, on the second floor, officials said.

There was no forced entry into the house and police found a weapon there, Ryan said.

Police said the motive was not yet known.

The double homicide brings the number of slayings in the city so far this year to 19, compared to 30 for the same time last year.

Staff writer Julie Shaw contributed to this story.