Police say they were called to a home on the 5200 block of Arbor Street in Philadelphia's Olney section for a domestic disturbance shortly after midnight Tuesday morning.
SWAT teams responded following information that a man in the home had a weapon and was holding a woman hostage inside the residence.
Shots were fired at about 1:45 a.m., but police say they are still figuring out if the suspect was shooting at officers or if he was trying to shoot himself.
Police returned fire and the man was found inside the home, shot in the chest.
Medics rushed him to the hospital in critical but stable condition.
The woman involved in the incident was not hurt and has been talking with police throughout the overnight.