A man and a woman were killed and three children were injured overnight when a school bus converted into a camper crashed and rolled northwest of Denver in Larimer County along Pingree Park Road, authorities said.

A 1-year-old girl was airlifted by helicopter to Children’s Hospital with serious injuries. Two boys, aged 7 and 3, were taken by ambulance to a hospital. The 47-year-old man from Greeley, and the 34-year-old woman from Loveland, were dead at the scene, Colorado State Patrol Master Trooper Gary Cutler said.

This single-vehicle crash happened shortly before 8:30 p.m. Tuesday night and Poudre Canyon firefighters went to the scene, maneuvering in rugged terrain, along with Larimer County Sheriff’s deputies, according to agency postings on Twitter.

Colorado State Patrol troopers were assisting in the aftermath. “They drifted off the road, and ended up rolling down the hill, about 400 feet,” Cutler said.

The relationships hadn’t been verified. The converted bus was designed to hold 15 passengers, he said. No other information was available.

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