A pregnant woman shot in the head Sunday night in Germantown remained in extremely critical condition at Albert Einstein Medical Center yesterday as police filed charges against two men allegedly responsible for wounding her.

Cops identified the woman as Bobbie Booker, 27, and filed charges against her boyfriend, Michael Thomas, 26, and Lamar Johnson, 22.

The incident began Sunday around 10 p.m. at the Queen Lane Apartments on Queen Lane near Pulaski Avenue when Thomas and other men, one of whom was Johnson, began arguing, police said.

It was unclear what the argument was about, investigators said.

Then, Thomas went into his apartment, grabbed his shotgun and began firing at Johnson, according to Homicide Capt. James Clark.

Johnson fired back at Thomas with a 9 mm handgun and one of the shots hit Booker in the head. The exchange of gunfire occurred outside, and Booker was hit while inside, according to police.

"She was pretty much an innocent bystander," Clark said of the incident. "She was just walking past her window. It's just very, very tragic."

Johnson was hit once in the leg during the gun battle, Clark said. He remained in stable condition.

Thomas and Johnson were charged yesterday with two counts each of attempted murder, aggravated assault and one count of aggravated assault on an unborn fetus.

Police said Booker was four months pregnant.

Clark said that both Thomas and Johnson, who have a "lengthy" past of prior contacts with police, will face murder charges if Booker dies.

The Queen Lane Apartments high-rise, owned by the Philadelphia Housing Authority, is where a PHA police officer, Craig Kelley, was shot in the side at point-blank range Feb. 17 while at his post inside a security booth.

Kelley survived and 17-year-old Zahir Boddy-Johnson was charged in the incident. *