The dead were identified by police as Vincent Thomas, 17, and a 20-year-old woman who was not identified, pending notification of next of kin. The wounded were identified as Comoniti Thomas, 18, and Brian Ruffin, 21.
Authorities believe that Ruffin may have recently moved into the apartment.
When police arrived, they found Ruffin critically injured in 10036 Ferndale, said police spokesman Capt. Benjamin Naish. Ruffin told police others were wounded in the dwelling at 10022.
"We found an additional three victims. Two people were deceased and one person was still alive," Naish said. "It does look like the people inside the house all knew each other."
Vincent Thomas and the woman were found by the back door. Neighbors said the woman may have been pregnant, which police could not confirm. Autopsies are scheduled for today.
Grieving family members arrived at the crime scene and became distraught as the bodies were removed.
"Oh my God," said one woman who identified herself as the mother of one victim. "This can't be happening to me."
At Vincent Thomas' home last night, his father, Carlton, said he was trying to figure out what happened.
"I'm really frustrated right now," he said while sitting on the steps of the family's rowhouse in West Philadelphia. "I don't want to talk to anybody."
At the West Philadelphia home of Comoniti Thomas, who is not related to Vincent Thomas, his mother, Annie, said she did not know why her son was in Bustleton yesterday morning.
After she heard that he had been shot, she went to Frankford Hospital-Torresdale Campus to see him. After waiting for hours, police allowed her to go up to his room. A detective told her that her son was handcuffed. She could only see his face and was told to leave after five minutes. Her son, she said, lived at home and worked as a handyman.
"Tell the detectives to get to work and find the person who put my son in critical condition," she said.
Authorities said the shooting may have been about a drug sale that went bad. Inside the house, police found numerous guns and substances believed to be powder cocaine and crack.
Police said that there have been complaints about drugs in the area recently and that narcotics authorities have been investigating.
Residents said the neighborhood, filled with two-story duplexes, has turned into a popular rental market, with residents of diverse ages from a mix of ethnic backgrounds. The neighborhood borders Red Lion Road, which is crowded with takeout restaurants, gas stations and a tavern.
Sybil Doroshow, 77, has been in the neighborhood for 17 years and said she was annoyed when she was abruptly awakened by what she thought was hammering.
She quickly learned otherwise.
"I was in shock," said Doroshow, who described the neighborhood as quiet. "These kinds of things just don't happen here."
Doroshow said she walks down the block several times a week and never saw anyone in the home where the shooting took place.
"Years ago, I knew everybody," Doroshow said. "In the past couple of years, it has become very transient."
Contact staff writer Barbara Boyer at 215-854-2641 or email@example.com.
Inquirer staff writer Julie Shaw contributed to this article.