A driver involved in a school bus crash Monday in Boulder County has been arrested on suspicion of being under the influence of drugs.

Elizabeth Burris, 39, of Longmont, was arrested after being released from Longmont United Hospital, where she was treated for injuries, according to the Colorado State Patrol.

Burris was booked in the Boulder County jail after her hospital release.

Burris is being held on suspicion of DUI, five counts of careless driving causing injury, two counts of vehicular assault and nine counts of child abuse, according to jail records.

The St. Vrain Valley School District bus with eight students aboard rolled onto its side in a single vehicle accident Monday afternoon in Boulder County. Injuries were reported, but officials said they were not life-threatening.

The Colorado State Patrol was called about the accident just after 4 p.m., said Trooper Nate Reid, a state patrol spokesman. The accident happened on Colorado 7 in the St. Vrain Canyon area, Reid said.

Preliminary reports of injuries range from minor to moderate, Reid said. The driver and five students were taken to Longmont United Hospital.

Two of the students sustained serious injuries with the remaining students received minor injuries. The students range in age from 7 to 15.

Boulder County Sheriff Joe Pelle described the bus crash as “heart-sinking.”

“We’re all very concerned when we have kids that are injured,” Pelle told the Daily Camera. “Fortunately, we didn’t have any real bad injuries.”

Students not taken to the hospital were taken to Lyons High School where district staff released them to a parent or family member.

The accident happened in a narrow section of canyon and the bus blocked traffic in both directions for several hours.

Kieran Nicholson: 303-954-1822, knicholson@denverpost.com or @kierannicholson