The body of a man found Monday afternoon in a Rosslyn parking lot was identified yesterday by Arlington police as Douglas R. Thornton, a 42-year-old District cab driver.

Police said an autopsy conducted yesterday showed Thornton, of 757 Hobart Pl. NW, died of head injuries and hypothermia. Police said they believe Thornton was last seen Friday.

Thornton was apparently robbed before he died, police said. They are classifying his death as a homicide.

Identification was made through fingerprints, police said, because of severe facial injuries.

A passerby found Thornton's body about 5 p.m. Monday in a parking lot of the Le Mar apartments, 1720 N. Quinn St., according to police. He apparently had been struck in the head with a blunt instrument, police said, but they said no weapon was found.

Police released few details concerning Thornton and his death. They said he was employed by a small taxicab company based in the District, but would not name the company. They said they had not been able to determine the time of his death.

A woman who answered the telephone last night at Thornton's home said no relatives would comment on his death.

The apartment complex parking lot where the body was found is behind a group of small stores at Wilson Boulevard and Quinn Street.

Several residents of Le Mar apartments said yesterday the discovery of the taxi driver's body in their quiet neighborhood was disconcerting.

"This came as quite a shock to all of us," said John Moyer, who has lived in the Le Mar apartments for almost 20 years. "I guess there is reason for concern when something as serious as this happens at our front door."

Several residents said they had moved to Arlington from the District because they felt it was safer, but were no longer sure that was true.

"I moved to Arlington for one reason. I lived in D.C. for four or five months and was mugged at gunpoint," said a resident who declined to give his name.