A paranoid schizophrenic woman barricaded herself inside an East Germantown apartment for almost 10 hours yesterday after she fired at a tenant, police said.

Scores of police officers spent much of the day trying to negotiate with Yvette Williams, 45, but eventually had to use tear gas to force her from the property on Ogontz Avenue near Church Lane.

The chaotic scene began at 10:09 a.m. and ended shortly before 8 p.m., police said. Williams did not fire at police, and it appeared that no one was injured in the long-running stand-off.

Police Commissioner Sylvester Johnson even showed up at one point during the intense negotiations.

Johnson, a trained hostage negotiator who has taught the delicate technique to law-enforcement officials across the country, said he decided to drive out to the stand-off to support cops on the scene.

Williams, who also suffers from multiple personalities, had a lengthy arrest record, including two charges of attempted murder, Johnson said. Police were cautious during their negotiations because she was barricaded inside with a gun.

"We are trying to save this woman's life," Johnson said at one point during the evening. *