What we know about California festival shooter Santino William Legan

The gunman who police say opened fire at a California festival, killing three and injuring 15 others, has been identified as 19-year-old Santino William Legan, CBS News has learned. Witnesses say the gunman had a "high-powered rifle" and was shooting randomly into the crowd at the annual Garlic Festival in Gilroy Sunday evening. Some witnesses said he suddenly appeared from behind a stage before beginning to shoot. He was quickly shot and killed by Gilroy police.

Police at the scene found a backpack belonging to Legan that contained rifle ammunition, CBS News has learned. Gilroy chief of police Scot Smithee confirmed the gunman opened fire with some type of rifle.   

"It was random," said witness Cheryl Low, who was working a vendor booth at the festival. "He shot one shot, then he put the clip in, and he just started moving shooting back and forth, walking towards our tent because that's where most of the people were in that area, and he started just shooting."

The ATF is tracing the ownership history and origins of the weapon and has canine units searching the area for shell casings, CBS News' Jeff Pegues reports.

Officers could be seen Tuesday morning leaving Legan's residence in Gilroy carrying evidence bags.

Smithee said the gunman used some kind of tool to cut through a perimeter fence to gain access to the festival, which the Associated Press reports draws about 100,000 each year. Smithee said the shooting appears to be random and police have not determined a motive.

The band Tin Man was doing an encore when gunfire erupted, CBS San Francisco reports. Singer Jack van Breen said he saw a man wearing a green shirt and grayish handkerchief around his neck fire into the food area with what appeared to be an assault rifle.Van Breen and other members of the band dove under the stage.

Van Breen told the station he heard someone shout, "Why are you doing this?" The person responded, "Because I'm really angry."

Smithee said police are searching for a possible second shooter based on witness accounts, but no description or more information was immediately available. 

Gilroy, a city of 50,000 some 80 miles southeast of San Francisco, is known as "The Garlic Capital of the World." The annual three-day festival features food, cooking competitions.

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

Source: www.cbsnews.com