Investigators are looking for the attackers involved in a shooting that killed a security guard who was credited with saving lives at a Southern California roller rink New Year’s Eve event.

Two others were wounded when gunfire broke out at about 2 a.m. at Cal Skate roller rink at 22080 Commerce Way in Grand Terrace, where about 200 people were celebrating the holiday. When sheriff’s deputies arrived, three people with gunshot wounds were found in the parking lot.

Two victims were taken to a hospital and one person was treated at the scene, according to the San Bernardino County Sheriff’s Department. Security guard Richard Williamson, 48, died at a hospital about an hour after the shooting.

Michael Marcoly, a big rig driver who was in his truck in the parking lot when the shooting broke out, said Williamson pulled out his gun and fired back at the assailants, who were firing toward the crowd.

"At first, I thought it was just people celebrating the New Year, firing guns," Marcoly said. "Then, when it hit my truck, it rocked my truck.

"He saved a bunch of kids and families, no doubt in my mind."

Williamson, known as Big Will, is the founder and owner of BW Security Services in Riverside. The company provides private security services to businesses and properties.

Calling him a "great man," his family set up a crowdsourcing page to collect donations.

The two injured men were described by the sheriff’s department only by their ages. One victim is 22 and the other is 28 years old. One of them was also a security guard at Cal Skate.

No arrests were reported Friday morning. Detectives have not yet publicly speculated on a motive.

Anyone with information is asked to call Detective Ryan Smith or Sgt. Jason Radeleff at 909-387-3589.