One person is dead and three others were injured following reports of a shooting near a Los Angeles-area polling station.
Los Angeles County fire inspector Gustavo Medina said one person was dead on arrival, two people had been airlifted to hospitals and a fourth is being treated after an incident in Azusa.
He was unable to say whether the four people had been shot.
An elementary school which is being used as a polling station is on lockdown.
Azusa police officer Jerry Willison said someone fired on officers at the scene, forcing them to take cover, but none of them were hurt.
No arrests have been made so far.