One dead after bus heading to Grand Canyon rolls over

A Las Vegas-based tour rolled over in northwestern Arizona (Mohave County Sheriff’s Office/AP)

One person was killed and two others critically injured when a tour bus heading to the Grand Canyon overturned in north-western Arizona, authorities said.

A spokeswoman for the Mohave County Sheriff’s Office said the cause of the incident on Friday afternoon was not yet known, but a fire official who responded said speed appeared to be a factor. No other vehicles were involved.