Police officers carry evidence bags from the family home of Gilroy Garlic Festival gunman Santino William Legan, July, 29, 2019, in Gilroy, Calif.
Police officers escort people from Christmas Hill Park following a deadly shooting during the Gilroy Garlic Festival, in Gilroy, Calif., on Sunday, July 28, 2019.

Last update: July 29 at 2:17 p.m.

Authorities in the western U.S. state of California say a gunman killed at least three people, including a 6-year old boy, at a popular food festival Sunday before being shot dead by police.

Police say the shooter appeared to randomly target people with a rifle at the Gilroy Garlic festival, about 170 kilometers southeast of San Francisco. Fifteen other festival-goers were wounded.

The shooter was identified in news reports as 19-year-old Santino William Legan. Authorities said they were searching Monday for a possible second suspect.

The festival, in the agricultural city of Gilroy, had security that required people to go through screening with metal detectors and bag checks. Police say the shooter cut through a fence to avoid the security checks.

People run as an active shooter was reported at the Gilroy Garlic Festival, south of San Jose, California.

Officers were present at the festival, and Gilroy Police Chief Scot Smithee said they quickly engaged the suspect and shot him dead.  Police say they are investigating the motive.

President Donald Trump on Monday expressed deep "sadness and sorrow" over the incident. "While families were spending time together at a local festival, a wicked murderer opened fire and killed three innocent citizens, including a young child. We grieve for their families," he said.

California Governor Gavin Newsom said in a tweet that he was grateful for the police response to the shooting and called the attack "nothing short of horrific."

The three-day garlic festival attracts around 100,000 people each year and features food and drink, cooking competitions and live music.

Smithee said the festival relies on thousands of volunteers each year and raises money for various organizations in the community.

"I think that the number of people that are willing to give their time for the betterment of other people is a wonderful thing. It is just incredibly sad and disheartening that an event that does so much good for our community has to suffer from a tragedy like this," he said.