SAN FRANCISCO (CBS SF) – A man remained in critical condition at a hospital Tuesday after apparently stumbling into the street and being hit by a truck in San Francisco’s South of Market neighborhood on Monday night, police and fire officials said.

The accident occurred about 9:35 p.m. Monday on Sixth Street between Howard and Harrison streets, police spokesman Sgt. Daryl Fong said.

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The pedestrian, believed to be a transient, somehow stumbled into the roadway, where he fell and was struck by a truck traveling north on Sixth Street, Fong said.

Fire department spokeswoman Mindy Talmadge said the pedestrian was trapped under the truck after the collision.

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He was taken to San Francisco General Hospital where he remained with life-threatening injuries Tuesday afternoon, Fong said.

The driver of the vehicle stopped and cooperated with authorities, and likely won’t be charged, he said.

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