This is an archived article that was published on sltrib.com in 2014, and information in the article may be outdated. It is provided only for personal research purposes and may not be reprinted.

A driver was in extremely critical condition Sunday following a collision between two tractor trailers.

A semi-truck pulling an empty trailer was eastbound on U.S. Highway 40 about 4:30 a.m. when for an unknown reason the empty trailer veered into the westbound lanes, Utah Highway Patrol troopers said.

A second semi, pulling a trailer filled with an unknown liquid, collided with driver side rear axle of the trailer, troopers said.

The driver of the second semi was flown by medical helicopter to University Hospital where he was listed in extremely critical condition.

The driver of the first truck was not injured.

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