SAN DIEGO (CNS) - A 20-year-old motorist who was allegedly behind the wheel of a sedan that rammed a car from behind in Mission Valley before slamming into several trees -- killing one of his three passengers -- pleaded not guilty Monday to charges of gross vehicular manslaughter, hit-and run causing death and driving on a suspended license.

Sajjad Ismael was ordered held on $500,000 bail.

According to the California Highway Patrol, the fatal crash happened on Interstate 8 about 1:30 p.m. last Thursday when a westbound 2001 Toyota Avalon driven by Ismael rear-ended a 2017 Toyota Prius at high speed near Waring Road. Following the impact, the Avalon veered into a center median, struck several trees and then careened back onto the freeway, where it skidded to a halt, CHP public affairs Officer Jake Sanchez said.

At that point, Ismael allegedly got out of the crumpled vehicle and fled on foot, leaving behind his three male passengers, one of whom died at the scene of the crash. The victim was identified as 18-year-old Isaac Garcia of El Cajon.

Medics took one of the other two young men who had been riding in the Avalon to Scripps Mercy Hospital with severe trauma. The third was treated for minor injuries at the scene.

The driver of the Prius, a 38-year-old woman, was unhurt, Sanchez said.

About 15 minutes after the crash, officers found Ismael in the area of Mission Gorge Road in Grantville and took him into custody.

At the time of the accident, the defendant was wanted on three warrants involving charges of DUI and driving without a valid license, authorities said.

Ismael will be back in court May 31 for a readiness conference and June 4 for a preliminary hearing. He faces 12 years in prison if convicted.