By CBSLA Staff

RIVERSIDE (CBSLA) — Authorities say a 68-year-old man remained in critical condition Sunday following a collision in Riverside.

Police say the man was traveling on a Harley Davidson motorcycle when he struck a large block of wood causing him to go down in the eastbound lanes of Arlington Avenue.

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The man was transported to a hospital where he was listed in critical condition. Police say he sustained major injuries.

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Police said it was unclear whether alcohol or drugs were contributing factors.

The cause of the crash is under investigation.

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Anyone with information regarding this collision is urged to call Riverside Police Traffic Det. Derouin (951) 826-8722.