An after-hours shoot-out between Los Angeles and Sacramento gangs in a parking lot of the State Fair in Sacramento left three people wounded--none of them gang members--and three men booked on drug or weapons charges, authorities said. Fair security officers and probation officers had been watching the gang members, Cal Expo general manager Joseph Barkett said. Shots were fired during a parking lot fistfight after the fair closed, slightly injuring two passers-by. Ninety minutes later, four youths in a car fired about 10 shots in the same parking lot, near a crowd of about 100, police Lt. Lawrence Gibbs said. An officer firing a warning shot into the ground was struck by a ricocheting bullet, authorities added. About 20 youths were rounded up for questioning. Two were booked for investigation of assault with deadly weapons and one on suspicion of cocaine possession. Neither they nor the victims were immediately identified.