The deadly spree started in Whittier where two people were shot. Their wounds were non-life-threatening, authorities said.
Authorities said a man was then wounded in a parking lot at Santa Gertrudes Avenue and Imperial Highway.
The fatal shooting took place near Santa Gertrudes Avenue and Alicante Road, by the La Mirada golf course, around 4 p.m. The man was found and taken to a local hospital, where he was pronounced dead, authorities said. Another person was injured during that shooting.
The two suspects then carjacked a person in Pico Rivera, authorities said.
Map shows span of La Mirada area shooting spree
The suspects were described as a man and woman in a green Nissan Pathfinder. The suspects' vehicle was located in Mayberry Park in Whittier about 3 miles away from the Biola University campus.
Biola University sent out an alert to students, saying there was no impact to the campus but for the community to be careful.
Authorities reported a separate scene involving a shooting in Santa Fe Springs at the Budget Inn along Firestone Boulevard, but did not say if the incident was connected with the La Mirada shooting spree.
A man and woman were shot at the inn and taken to UCI Medical Center in unknown conditions.
Another shooting scene was also reported at Carmenita Road above the 5 Freeway. Authorities said the scene was related to the Budget Inn shooting, but did not elaborate on how.
The investigation was ongoing.