Chester City police are investigating the suspicious deaths of four people who were found in a rowhouse last night.

Authorities originally believed the deaths were caused by carbon monoxide, but investigators have ruled that out.

"It's suspicious until we hear further from the medical examiner," Chester City Police Chief Floyd Lewis said.

Lewis said police crews were dispatched to the rowhouse on the 900 block of Keystone Street about 7 p.m. Inside the second-floor apartment, they found the bodies of a man, two women and a toddler.

The bodies were found in a living room and a bedroom. The identities of the victims were not immediately known. Police said the adults appeared to be in their 20s.

Police said there were no signs of forced entry into the home.

Police reports indicated that medics were dispatched to the home about 8 p.m. after receiving a call that a person was ill there. They arrived to find four people dead.

Kevin Nguyen, 30, who works at the nearby T & L Nail Salon on the 3100 block of West Ninth Street, said he was closing the shop about 8 p.m. when he heard sirens and saw a line of police cars and ambulances driving past his windows.

"I don't know what happened," Nguyen said. "But I see the cops. There were a lot of police cars."

Contact staff writer Suzette Parmley at 215-854-2594 or