BERKELEY (CBS SF) – A fatal collision on eastbound Interstate Highway 80 early Monday morning may have been caused by drowsiness, a California Highway Patrol spokesman said.

At about 5:15 a.m. Monday, a black Nissan sedan disabled in the fast lane or the lane next to the fast lane on eastbound Highway 80 east of the Gilman Street exit with its hazard lights on was struck from behind by a silver Volkswagen sedan, according to CHP spokesman Alex Frazer.

The male driver of the Nissan was pronounced dead at the scene and the male driver of the Volkswagen was taken to Kaiser Permanente Richmond Medical Center to be treated for minor injuries, Frazer said.

The Volkswagen driver told investigators that he may have been falling asleep at the wheel at the time of the collision, according to Frazer.

However, it doesn’t appear that alcohol or drugs were factors in the fatal collision, Frazer said.

The name of the Nissan driver who died is being withheld pending notification of his next of kin, an Alameda County coroner’s spokeswoman said.

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