Bell Gardens police said the suspect fired at officers after he and another suspect ran away from them when officers attempted to contact them at about 9:30 a.m.
Officers fired back at the suspect, who barricaded himself inside a house for several hours, police said.
There was a large police presence in the area of Jaboneria Road and Eastern Avenue. Officers were told the man was armed and threatened to kill himself.
The standoff led to a lockdown of local schools and the neighborhood.
Video shows SWAT officers firing tear gas and flash-bang grenades later in the evening at approximately 7:16 p.m. The officers entered the residence and discovered the man was dead from a gunshot wound.
The suspect was originally the subject of an arrest warrant.
He was not immediately identified.