Police said a second victim was shot as he ran from the scene in the city's Koreatown section, the Los Angeles Times reported.
Police said they were looking for three suspects in a white sport utility vehicle that was used to run down the bicyclist, whose name was not reported.
There was no initial indication whether the men in the SUV knew the cyclist who was shot to death, or whether the other victim was just in the wrong place at the wrong time, investigators said.
A Los Angeles Police Department spokeswoman said investigators had not determined what motivated the attack.
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