Three brothers from Clearfield were killed in a car accident near Cortez, Colo., Sunday morning.

Killed were:David J. Sellers, 22;

Heathe Sellers, 17;

Rick J. Sellers, 11.

The brothers were traveling north on I-666 near Cortez about 8:30 a.m., according to a Colorado State Police report.

David Sellers was driving the 1997 Ford two-door car when it drifted into on-coming traffic. The Sellers car hit the side of a semi tractor-trailer near the tires of the trailer, the report said.

The Ford spun around and skidded to the right, where it was hit broadside by another car heading south, the report said. The impact was so great that, despite wearing seat belts, David and Rick Sellers, who were in the front seats, were partially ejected from the car, Colorado state troopers said.

"It's kind of unusual, where seat belts are actually used, to be ejected," said Gordon DeBruin, communications supervisor for the state police in Durango. "They weren't thrown from the vehicle."

David and Rick Sellers were pronounced dead at the scene of the accident, which investigators described as "intense" and "gruesome."

Heathe Sellers, who was sitting in the back seat, was flown to San Juan Regional Medical Center in New Mexico. He died about 4:40 p.m.

The bodies of all three boys were taken to a Cortez mortuary, but they will likely be returned to Clearfield on Tuesday.

Colorado State Police aren't sure what caused the Sellers car to drift into oncoming traffic. DeBruin said there were no apparent mechanical failures and weather wasn't a factor.

"In a case like that you may never know (the cause)," he said.

Davis School District sent crisis teams to Clearfield High School and South Clearfield Elementary Monday to talk with students who were close to Heathe and Rick Sellers.

At the high school, team member Lorie Coates said the core team of a dozen district psychologists, social workers and counselors was being augmented by high school faculty members who are trained in crisis intervention.

"The team tries to talk with students to dispel any rumors and identify those students who might be a risk (emotionally) and may need more help," Coates said.

"We make sure those students have friends and family they can talk to for support and have a plan for the next few days," she said.

Coates said the core crisis team usually spends a day or two in a school to deal with such situations and then follows up as needed.

"But we can spend more time, depending on the needs of the school," she added.

School officials were not available to provide information on the deceased teen and did not permit interviews with students.

South Clearfield Elementary principal Dick Close said a team of eight mental-health professionals arrived at his school this morning, meeting with individuals as well as small groups of students and entire classrooms.

"They've been very helpful," he said.