Police on Monday identified a 19-year-old California man as the gunman who opened fire with an assault rifle at a garlic festival in Gilroy, California, killing three people and wounding about a dozen.

Axar.az reports citing Reuters that Santino William Legan, 19, cut through a fence at the festival on Sunday evening and shot people, seemingly at random, with an “AK-47-style” assault rifle, Gilroy Police Chief Scot Smithee told reporters. Legan was fatally shot within about a minute by police.

“It could have gone so much worse so fast,” Smithee said, noting that the festival, which takes place about 30 miles (48 km) southeast of Silicon Valley, is attended by thousands of visitors.

President Donald Trump described the gunman as a “wicked murderer” during an event at the White House and asked Americans to pray for the victims.

The gunman was believed to have cut through the fence in order to evade metal detectors and other security measures at the entrance, police said.

Legan appeared to post a photograph from the festival on his Instagram account shortly before the shooting, with captions expressing his disdain for the event.

“Ayyy garlic festival time,” he wrote beneath a picture of people walking through the festival grounds. “Come get wasted on overpriced trash.”

Another photograph posted on Sunday showed a sign warning of a high danger of forest fires. Its caption urged people to read “Might is Right,” a racist and sexist treatise written in the 19th century.

Weapons of any kind are prohibited, according to the event’s website, which also said anyone wearing clothing or paraphernalia indicating membership in a gang, including a motorcycle club, would be refused entry.