A Huntington Beach man pleaded not guilty last week to charges that he drove on a suspended license and hit another driver, causing him severe brain injuries, then left the scene, according to the Orange County district attorney's office.

Oscar Paz, 31, was allegedly speeding in his Volkswagen Jetta around 5 a.m. Dec. 11 on the 22 Freeway when he rear-ended 66-year-old G. Krishnan's Nissan Pulsar. Paz's license had been suspended when he failed to appear in court for a speeding ticket.

Krishnan's car thrust across the freeway and hit the center divider, prosecutors said.

Paz then allegedly exited the freeway without offering to help Krishnan, parked his car at a nearby strip mall and fled on foot.

He called his wife for a ride home, prosecutors said.

Seven hours later, Paz turned himself in to the California Highway Patrol's Westminster office, which investigated the accident and found his parked vehicle.

Krishnan was transported to UC Irvine Medical Center; he remains in a coma and critical condition, according to prosecutors.

Paz is charged with one felony count of hit-and-run with injury and one misdemeanor count of driving on a suspended license. He pleaded not guilty Dec. 14 and faces a maximum sentence of three years in prison if convicted.

He is held in lieu of $50,000 bail and is scheduled for pre-trial Dec. 21 in Central Justice Center in Santa Ana.

mona.shadia@latimes.com

Twitter: @MonaShadia