Officer Kills Man Who Attacked Partner : Crime: Police say bulletproof vest thwarted suspect’s knife assault. He often created disturbances, they say.

A Pasadena police officer shot and killed an apparently deranged man who attempted to stab the officer’s partner twice in the chest as they answered a 911 call at an apartment Wednesday morning, authorities said.

The officer who was attacked, Al Campbell, 25, was not injured because he was wearing a bulletproof vest, Police Lt. Frank Wills said. Had the three-year veteran not been wearing it, “it definitely could have been fatal,” he added.

After the shooting, a Los Angeles County sheriff’s investigator displayed a six-inch paring knife that had been bent by the impact with the bulletproof vest.

Campbell’s partner, whose name was not immediately released, fired twice at the attacker, identified as Edward Ecxaze Hernandez, 21.

Wills said Hernandez stayed with his mother and sister, who live in the South Marengo Avenue complex where the shooting took place. The women were not at home at the time of the incident.

He said officers did not know if the man had a permanent residence elsewhere.

Bridget Connell, manager of the complex, said she had received complaints in recent months that Hernandez was disturbing tenants and peeked in their windows. She said he appeared to be disoriented.

“He made no sense when you talked to him,” the manager said.

Connell said she had talked to Hernandez’s mother, who “just said that he was sick.”

The manager said she had served an eviction notice on the mother and her daughter Saturday because of the disturbances caused by Hernandez.

In the early morning hours before the shooting, Pasadena officers were called to the 20-unit courtyard complex twice by neighbors who reported that a man was acting suspiciously.

On one occasion, Wills said, “Officers attempted to detain him, but he ran away.”

Shortly before 8 a.m., someone dialed 911 from the Hernandez family’s rear second-floor apartment but said nothing, Wills said. The address appeared automatically on a police dispatch screen, however, and Campbell and his partner responded.

Wills said the officers forced their way into the apartment and were attacked as they entered.

The lieutenant said Hernandez had been taken into custody on two occasions by Pasadena police and ordered to undergo a 72-hour psychiatric evaluation, most recently on Sept. 4.

After Wednesday’s shooting, the beige stucco-and-brick complex was roped off as a Pasadena police team began collecting evidence.

Investigators from the Sheriff’s Department and the district attorney’s office conducted independent reviews. Wills said Pasadena police guidelines require an outside probe of all officer-involved fatal shootings.