Officer won't be charged in killing of unstable black man

FILE - In this Sept. 27, 2016 file image made from from bystander video provided by the El Cajon Police Department, Alfred Olongo, right, is seen pointing what was later determined to be a bulky electronic cigarette device at El Cajon, Calif., police officer Richard Gonsalves during a confrontation at an El Cajon strip mall. Moments later Olongo was shot and killed. San Diego County District Attorney Bonnie Damais announced Tuesday, Jan. 10, 2017, that no criminal charges will be filed against Gonsalves. (El Cajon Police Department/San Diego County District Attorney's Office via AP, File) (The Associated Press)

Prosecutors say criminal charges won't be filed against a California police officer who killed a mentally unstable black man he thought was aiming a gun.

San Diego County District Attorney Bonnie Dumanis announced Tuesday that her office determined the shooting of 38-year-old Alfred Olango last September was justified because the officer thought his life was in danger.

Video showed Olango in a shooting stance, with both hands wrapped around a cylindrical object that turned out to be an e-cigarette device.

The shooting in El Cajon prompted days of demonstrations and Olango's relatives filed wrongful-death claims with the city. They said the Ugandan native had a breakdown after a friend's death.

Olango was shot as police answered calls from Olango's sister saying he was acting erratically and needed mental health care.