Roughly 20 minutes later, Dorner allegedly fired on two police officers in the nearby city of Riverside, killing one and wounding another. On Sunday, authorities identified the slain officer as Michael Crain, an 11-year veteran officer.

LAPD guarding 50 police families

Authorities say Dorner spent at least two days in the San Diego area after the shooting of Quan and her fiance. Dorner's ID and some of his personal belongings were found Thursday at the San Ysidro Point of Entry at the U.S.-Mexico border, according to the affidavit.

Border patrol agents have been searching cars crossing into Mexico for signs of Dorner, while authorities have searched a home Dorner owned in Las Vegas and one owned by his mother in La Palma, California.

Two sailors reported that Dorner, a former Navy lieutenant, approached them at the San Diego-area Point Loma Naval Base, and local police allege he attempted to steal a boat.

And Monica Quan's father told investigators that someone identifying himself as Dorner called him Thursday and told him he "should have done a better job of protecting his daughter," the federal affidavit states. Investigators traced the call to Vancouver, Washington, but based on the timing of other sightings, they don't believe Dorner was in Vancouver at the time, the affidavit states.

Beck said the LAPD is now guarding the families of more than 50 police officers. Officers guarding one house early Thursday shot and wounded two women who were driving a pickup similar to Dorner's, something Beck called a "tragic, horrific incident."

Beck said that the shootings of Margie Carranza, 47, and her mother, Emma Hernandez, 71, occurred a day after the manhunt for Dorner began and that the officers were under enormous pressure.