Man Dies After Police Chase Ends in Canal : Fatality: Hypothermia and drug use are suspected causes of death, autopsy reveals. Suspect jumped into a flood control channel.

A 34-year-old man, who had led police on a high-speed chase that ended when he jumped into a flood control channel, apparently died of a combination of hypothermia and drug use, authorities said Sunday.

Fountain Valley Police Lt. Robert Mosley said an autopsy Sunday showed that Richard John O’Gorman of Huntington Beach had two collapsed lungs, which might have resulted from a mix of heroin in his body and exposure to the cold water. Police said they found a hypodermic needle and fresh blood in his car, and that relatives told them he was a heroin addict undergoing treatment.

“It appears he had injected himself with some kind of narcotic just prior to the pursuit,” Mosley said. “But the actual cause of death probably won’t be known for six weeks, when the coroner issues a report.”

The incident started shortly before 10:30 p.m. Saturday when an officer saw a car without headlights driving at a high rate of speed in a parking lot at Los Amigos High School, police said. The driver fled, leading three squad cars and a police helicopter on an 80-m.p.h. chase through Fountain Valley and Huntington Beach.

The chase ended near the Edison power plant in Huntington Beach when O’Gorman crashed into a chain-link fence at a large flood control channel at Magnolia Street near Pacific Coast Highway.

Police said he dived into the channel and refused to surrender until a police dog was sent in and bit him on both arms during a struggle in the water.

“The dog got him to come to the shoreline, and then he complied with police commands and was taken into custody,” Sgt. Norm Satterfield said.

Paramedics administered first aid to O’Gorman, who was taken to Hoag Memorial Presbyterian Hospital in Newport Beach, where he was pronounced dead.

He recently had been paroled from state prison after serving a sentence for armed robbery. The Orange County district attorney’s office is investigating the death, as it does whenever a suspect dies during an arrest or when in police custody.