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.

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

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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