The Los Angeles Police Department is investigating how a woman who had filed a domestic abuse report was slain in her Mid-City apartment late Wednesday night as officers were watching it while on the lookout for the suspect.

According to LAPD sources, the chain of events began when the unidentified woman went to the Wilshire Division police station to report that she was a victim of domestic abuse.

Officers who specialize in domestic violence talked to the woman and, at some point, drove her back to her home near Cochran Avenue and Pico Boulevard. Law enforcement sources said the officers went into the apartment with the woman to make sure the suspect was not there. They thoroughly checked the apartment and then went to their car.

The officers decided to keep watch on the street, worried that the suspect might come to cause trouble, sources said. Police believe the man sneaked into the apartment through a small back window, sources said, possibly scaling the roof to get there. The sources spoke on the condition that they not be named because LAPD policy does not allow public comments on open cases.

The officers heard the woman's screams, ran into the apartment and saw a man stabbing the woman. They opened fire, fatally wounding the attacker.