Three people — including at least two high schools students — were killed early Monday in a crash on Highway 101, according to the Santa Barbara City Fire Department.

Another person suffered major injuries in the collision, which occurred at about 12:45 a.m. on the southbound freeway at Castillo Street, the California Highway Patrol said.

All lanes of southbound Highway 101 remained closed for several hours following the wreck, the CHP said, leading to major traffic tie-ups in the area.

As of 1:30 p.m., the Castillo Street offramp had been reopened, and all lanes of the freeway were reported flowing again, the CHP said.

The accident occurred when a Mazda sedan driven by Erick Hoel August, 20, of Los Angeles veered to the right for unknown reasons and struck a guardrail, the CHP said.

The vehicle overturned, coming to rest in the middle lane and facing the center divider.

Moments later, a Ford Mustang driven by Kimberly Ann Kreis, 52, of Santa Barbara slammed into the left side of the Mazda, causing two people in that vehicle to be ejected, the CHP said.

The three people killed — a male and two females — and the critically injured patient were in the Mazda, fire said Battalion Chief Lee Waldron.

Arriving firefighters found two victims in the roadway, and two had to be extricated from the vehicle, he said.

Those killed were Danielle Nicole Murillo and Jessica Lee Leffew, both 17 and from Torrance, and Brian Adonay Lopez, 20, of Los Angeles, the CHP said Monday afternoon.

Two of the victims were seniors at North High School in Torrance in Southern California, according to the Torrance Daily Breeze.

School officials in Torrance did not immediately release the names of the students, citing an ongoing investigation, the newspaper reported, but both students reportedly were seniors.

At North High on Monday, a team of grief counselors was on hand to console the students. Principal Ron Richardson sent out a bulletin to families.

“It is very difficult to lose a member of our community,” he wrote. “We are very heartbroken by the tragic loss of two of our students. We would like to extend our heartfelt sympathies to their families, teachers, classmates and friends.”

Kreis did not appear to be seriously injured, Waldron said.

She subsequently was arrested on suspicion of DUI, and booked into the Santa Barbara County Jail, the CHP said.

August was taken to Santa Barbara Cottage Hospital, and was listed in critical condition.

Check back with Noozhawk for updates to this story.

— Noozhawk executive editor Tom Bolton can be reached at .(JavaScript must be enabled to view this email address) . Follow Noozhawk on Twitter: @noozhawk, @NoozhawkNews and @NoozhawkBiz. Connect with Noozhawk on Facebook.