The Alameda County District Attorney’s Office has charged three people in connection with the shooting death of security guard and former police officer Kevin Nishita, Oakland police announced Wednesday.

Two of the three people charged are in custody, police said. Investigators are trying to locate the third person.

Nishita, 56, was shot in an attempted armed robbery of a news crew in downtown Oakland on Nov. 24 and died days later.

Oakland police Chief LeRonne Armstrong is scheduled to hold a news conference Thursday afternoon to discuss the case.