SANTA ANA (CBSLA.com) — A motorcyclist died from injuries he suffered after a collision on the 55 Freeway on Sunday morning, and a person who came to his aid was critically hurt when struck by a suspected drunken driver, Santa Ana police said.

The crash occurred when the motorcycle struck the rear of a car heading south on the 55 Freeway, just north of Warner Avenue, according to Santa Ana police Cmdr. Jason Miramontes. As a result of the 12:53 a.m.crash, the motorcyclist went off the freeway and landed on Ritchey Street, where a motorist saw him and went to help.

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Miramontes said when police arrived at the scene, the motorist who had been giving aid to the injured man crossed the street to meet them and was struck by the suspected drunken driver, who also hit the motorcyclist.

The man who was rendering aid suffered moderate to severe injuries, but is expected to survive. The motorcyclist was pronounced dead at a hospital at 9 a.m., and police said he suffered the fatal injuries when driving off the freeway.

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The driver who struck the good Samaritan and the motorcyclist was arrested on suspicion of drunken driving, Miramontes said.

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