POMONA (CBSLA) – A bicyclist was struck and killed by a semi-truck in Pomona early Wednesday morning.

The collision occurred in the 2800 block of Pomona Boulevard at 4:22 a.m., Pomona police said. The victim was pronounced dead at the scene. The circumstances of the collision were not confirmed.

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The L.A. County coroner’s office said the victim was a man in his 40s. His name was not released.

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The truck driver remained at the scene and cooperated with investigators, police said.

Pomona Boulevard was shut down in both directions for several hours.

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