Investigators say Twinn and a family member people were driving north on Fruit Avenue, between Ashlan and Dakota, when a light-colored SUV pulled up behind them and started shooting.
Twinn pulled into an apartment complex to escape, but detectives say several shots were fired into the vehicle.
Twinn was rushed to the hospital, where he later died from his injuries. The condition of his family member was not released.
Police say the incident was a senseless act of violence. Investigators are asking the public's help finding the shooter.
Anyone with information is asked to contact the Fresno Police Department.
The video above is from an earlier broadcast.