Four people including gunman killed in shooting at California food festival

A gunman killed at least three people at a California food festival on Sunday before being shot dead by police, and police were hunting for a second person they believed was involved in the killing.

Some 15 people were wounded during the mass shooting at the three-day Gilroy Garlic Festival in northern California, some of them hurt in the crush of bystanders trying to flee, police said.

Police reached the scene within a minute of the first shots ringing out at 5:45 pm and officers shot and killed the gunman moments later, according to Scot Smithee, who heads the Gilroy Police Department.

A second person, "was involved in some way, we just don't know in what way," Smithee said late on Sunday.

"We have no idea of a motive," he added.

Smithee said the gunman had cut through a fence to get into the annual Garlic Festival in Gilroy, 48 kilometers southeast of the city of San Jose.

Footage uploaded to social media appeared to show festival attendees scattering in fear and confusion as loud popping sounds could be heard in the background.

"What's going on?" a woman can be heard asking on one video. "Who'd shoot up a garlic festival?"

Aerial footage showed the festival grounds apparently deserted but with many emergency and police vehicles on surrounding streets and police in bullet-proof gear.

"It's just incredibly sad and disheartening that at an event that does so much good for the community had to suffer from a tragedy like this," Smithee said.