MISSION VIEJO (CBSLA) — A Costa Mesa fire captain was critically injured in Mission Viejo Saturday when he was struck while riding his bicycle by a van driven by a man arrested on suspicion of driving under the influence of a controlled substance, authorities said.

The crash was reported just after 8 a.m. on eastbound Alicia Parkway near Via Burgos, Orange County sheriff’s spokeswoman Carrie Braun said.

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Van driver Stephen Taylor Scarpa, 25, of Mission Viejo was evaluated for possible DUI at the scene and subsequently arrested on suspicion of felony DUI, Braun said. He was booked into the Orange County jail in lieu of $100,000 bail. Multiple prescription medications were found inside his van, she said.

The bicyclist was taken to a hospital for treatment of head and body trauma, Braun said. He was identified as Costa Mesa fire Capt. Mike Kreza, an 18-year veteran of the department and off-duty at the time of the crash.

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“Our entire Costa Mesa Fire & Rescue family is immensely saddened by the news that one of our own was involved in an accident this morning,” Chief Dan Stefano said. “We are working together to support the family and each other.”

Anyone with information on the crash was asked to call the Orange County Sheriff’s Department at (714) 647-7000 or Crime Stoppers at (855) TIP-OCCS.

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(© Copyright 2018 CBS Broadcasting Inc. All Rights Reserved. City News Service contributed to this report.)