Witnesses said Martinez seemed alert and conscious immediately after the accident, but he died a few hours later at St. Francis Medical Center.
"I heard cars honking, and I came to look and I saw the guy on the floor," said witness Mario Lava.
Lava was just one of many people who saw a man in a mangled motorized wheelchair lying in the middle of the street.
Witness Mariene Dixon said she would always see Martinez crossing the busy section of Martin Luther King Jr. Boulevard.
Police have no leads on the hit-and-run because the driver took off immediately after hitting the victim.
Anyone with information is urged to call the L.A. County Sheriff's Century station at (323) 568-4800. Eyewitness News Reporters Subha Ravindhran and Jovana Lara contributed to this report.
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