SACRAMENTO -- Police and ambulances raced to a shooting at a food festival in California on Sunday, with three people reported dead and several injured, and video posted on social media showing people at the event running for cover as shots rang out.

A local city councilman, Dion Bracco, told The New York Times three people were killed and 12 injured in the shooting on the last day of the Gilroy Garlic Festival, an annual three-day event south of San Jose. He did not know if the 12 injured included the three fatalities, the newspaper said.

One suspect was in custody, Bracco said.

“They don’t know if there were more, so they have to treat it as an active situation,” he told the newspaper. “We have police out here from as far away as San Jose.”

NBC Bay Area had reported that ambulance crews were told 11 people were “down” after the shooting.

Local hospital officials did not immediately respond to requests for comment. Aerial footage showed the festival grounds apparently deserted but with many emergency and police vehicles on surrounding streets and police in bullet-proof gear.

“Be careful and safe!” U.S. President Donald Trump wrote on Twitter.

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?”

California Governor Gavin Newsom said his office was monitoring the situation closely. “This is nothing short of horrific,” Newsom wrote on Twitter.

Fireworks

Evenny Reyes, 13, told the San Jose Mercury News that at first she thought the gunfire was fireworks. But then she saw someone with a wounded leg.

“We were just leaving and we saw a guy with a bandana wrapped around his leg because he got shot,” Reyes told the newspaper. “There was a little kid hurt on the ground. People were throwing tables and cutting fences to get out.”

Another witness, Maximo Rocha, a volunteer with the Gilroy Browns youth football team, said he saw many people on the ground, but could not be sure how many may have been shot and how many were trying to protect themselves.

He told NBC Bay Area that “quite a few” were injured, “because I helped a few.”

One video posted on Twitter showed a blood-spattered woman sitting in the back of a semi-trailer and telling a man she had been shot in the hand.

Stage hand Shawn Viaggi told the Mercury News he heard gunshots and saw bullets hitting the ground. “I called out, ‘It’s a real gun, let’s get out of here,’ and we hid under the stage,” Viaggi told the newspaper, adding that he saw police officers trying to resuscitate one man.

Founded in 1979, the Gilroy Garlic Festival features food, drink, live entertainment and cooking competitions. It says it is hosted by volunteers and describes itself as the world’s greatest summer food festival.

It was being held at the outdoor Christmas Hill Park, where weapons of any kind are prohibited, according to the event’s website.

To provide a safe, family-friendly atmosphere, it said, entry was refused to anyone wearing clothing or paraphernalia indicating membership in a gang, including a motorcycle club.

Festival officials did not immediately respond to requests for comment.

Gilroy is about 30 miles (48 km) southeast of San Jose.