A tennis pro, self-styled master natural healer and crystal therapist was charged Monday with trying to run down and kill four bicyclists last week in San Francisco.

David Mark Clark, 39, of Albany was arrested Friday after he went to Albany police to report that his Nissan Rogue sport utility vehicle had been taken at gunpoint. The Rogue was abandoned at 17th and Missouri streets Wednesday night after the hit-and-run driver struck his fourth victim and crashed the vehicle.

Clark, who has no criminal record, was charged Monday in San Francisco Superior Court with four counts of attempted murder, assault with a deadly weapon and three counts of battery causing serious injury. He is being held without bail in the psychiatric unit of the county jail.

One of the victims remains hospitalized at San Francisco General, where he is in serious condition.

The investigator in the case, Sgt. Jon Kasper, said police have yet to determine a motive for the attacks. Clark has not given police a statement, he said.

Clark recently applied for a job at the San Francisco Tennis Club, said Weston Reese, the club's tennis director. Clark taught a lesson as part of the interview process and appeared to be qualified, having worked at a club in New York state, Reese said.

"His credentials were very good. He seemed like a good guy," Reese said.

Clark was scheduled for a follow-up interview Thursday but didn't show up, Reese said. That was one day after the hit-run driver mowed down his victims in the Mission District and on Potrero Hill.

Steve Owens, head pro at the Sawmill Club in Westchester County, N.Y., said Clark had worked as a pro for seven years there with no problems.

"He was very into his job," Owens said. "He taught private clinics, coached teams and taught private lessons."

He added, "We are kind of trying to hope this is a big mistake, that it wasn't him driving the car."

In addition to being a tennis pro, Clark boasted on a Web site that he was a crystal therapist, a "Reiki master," referring to a natural healing technique, and a "priest in the Order of Melchizedek." The order is described on one Web site of believers as "composed of evolved beings who have dedicated themselves to the work of promoting spiritual growth."

"After an energetic awakening in 2006, David has committed his life to the service of others through healing," Clark's entry reads.

One member of the spiritual community said Clark was gentle and a spiritual healer, not a destroyer.

"That's a shock," said Valencia Chan, owner of Angel Light Books and Gifts in Berkeley. She listed his biography for a time on her Web site.

"Since I haven't seen him in so long, I took him off," Chan said. "He was very easygoing, very mild-mannered. He was very spiritual - he bought a lot of spiritual books."

On his tennis Web site, Clark says he has 15 years of experience as a pro and specializes in "Tenergy," combining tennis, exercises and yoga.