An Oakland, California, man killed four police officers and wounded another in two separate shootings Saturday that began with a traffic stop and ended with a gun battle.

Two motorcycle police officers stopped a car driven by Lovelle Mixon Saturday afternoon.  Mixon fired on the officers, killing one and wounding the other, who was declared dead on Sunday.

Mixon ran from the scene of the shooting.  He was wanted for violating parole on a charge of assault with a deadly weapon.

Two hours later, police received a tip that Mixon was inside an apartment building.  As officers did a search, Mixon again opened fire, killing two more police.  A third officer was grazed by a bullet.

Police returned fire and killed Mixon.

California Governor Arnold Schwarzenegger offered his condolences to the families of the dead officers and ordered the state's flags lowered to half-staff.

Some information for this report was provided by AFP, AP and Reuters.