DETROIT - Ruth Wahl spun her car into the parking lot of Vernor Elementary School and cut the engine.

It was midnight in the Motor City, and her shiny white Suzuki Sidekick, the first car she ever loved, glimmered in the moonlight.

Wahl, a 22-year-old drugstore cashier, and three friends were just opening a beer when three young men in a brown station wagon entered the lot and drew near.

"Nobody comes here," Tone Davis, a slender, pony-tailed chorus dancer, warned Wahl. "We better go."

But the Suzuki lost a race down deserted streets.

The wagon finally trapped it against a curb.

A single gunman jumped out.

"Gimme your truck, bitch," the gunman shouted.

Then he opened fire, shooting Ruth Wahl to death.

From the city that put the world on wheels comes terror to stand Detroiters' hair on end as a growing number of armed thieves, called "carjackers," are targeting occupied vehicles instead of empty ones.

In what authorities in this city of 1.2 million describe as an epidemic of summer violence, armed robbers are commandeering cars stopped at traffic lights, restaurant parking lots, automatic-teller machines, pay telephones and self-serve filling stations.

More than 300 carjackings have occurred since mid-July - 205 in one 21-day period - say police, who have formed a task force and added investigators to the Robbery Division to combat the crime. But despite 145 arrests and charges against 32 people, carjackings are continuing at a maximum rate of 10 a day.

"It's like a new disease," said Deborah Cohen, 24, a communications specialist for the city's United Way campaign, "one more thing we have to worry about along with everything else."

Although downtown Detroit has been hit hardest, the suburbs are not immune. There have been 31 carjackings in 40 suburban communities since May, according to a survey by The Detroit News.

Several restaurant owners in downtown Detroit say they were driven to bankruptcy amid complaints from customers afraid to drive downtown.

For a city already plagued with a national reputation for violence - "Detroit: Where the weak are killed and eaten," a popular T-shirt boasts - the carjackings are another smudge on a tarnished image, another source of fear and loathing and a twist on the general admonition to "drive defensively."

"I'm real worried for my daughter. She goes to Wayne State University, in and out of Detroit all the time," said Donna Livengood, a cashier at the Shell Self-Serve Food Mart in suburban St. Clair Shores. "The scary part is, it seems to be escalating."

Gwen Love, 25, said it was not unusual to see cars coasting slowly but not stopping at traffic lights as drivers eye pedestrians and one another warily.

"And now if it's Tuesday, and I don't need but maybe $3, I fill the tank anyway," Love said.

Law-enforcement officials theorize that the availability of guns coupled with advances in car-alarm and anti-theft technology may inadvertently have set the stage for the crime craze of the moment in Detroit.

Officials say the crime itself is not new. Car thefts at gunpoint have been around since Bonnie and Clyde. But it is more virulent this year, as cars of every make and model are being preyed upon, day and night, and massive news coverage of the incidents seems to have spawned a crop of criminal copycats.

Among the recent victims:

-- A 29-year-old woman and her husband who were stopped in afternoon traffic when a gun-toting teen-ager forced them from their 1990 Mustang.

-- A 23-year-old man who was shot to death after he refused to surrender his 1986 Oldsmobile at a self-service car wash.

-- An 18-year-old woman whose 1984 Topaz was snatched at a self-service gas station.

-- An off-duty Detroit police officer who was shot and critically wounded in her driveway.

-- One man was shot even after he handed over the keys.

"We're dealing with a street stick-up man," said Robert Hislop, commander of the Detroit Police Major Crimes Division. "The victim happens to be in a car. The car becomes an instrument for escape. But the crime is not directed at the car. It's a crime of violence and opportunity targeted against a person."

Be aware

Police have advised motorists to pay extra attention to their surroundings, to drive with windows up and doors locked, to always have enough gas to get to a safe location, to drive to a hospital, fire station or police station if they are being followed (some robberies have occurred after bump-rob-and-run accidents) and not to resist if an armed confrontation occurs.

Some cars have been stripped for parts in chop shops or used to pay off drug-dealing debts. But 70 percent of the cars are abandoned and recovered in relatively good condition, police say.

"Which is why we don't like the term carjacker," Hislop said. "If I stick you up on the corner and take your wallet, are you going to call me a `walletjacker?' "

If the term to describe gunpoint car theft is controversial, so are the tactics to combat it.

Police in neighboring Oakland County have deployed decoys to play the role of unsuspecting motorists, but Detroit police believe the use of decoys will only escalate the violence.

"We don't feel it will deter the street hold-up man. It will just make him more hinkey and nervous," Lt. Jeanne Miller said. Decoy work, she added, is also manpower intensive because a surveillance team of four or five officers is required for each "pigeon" on the street.

"I've worked undercover narcotics. I'm not afraid to go undercover," Miller said. But the criminals "are going to come up to the car and put a gun to your head, and there isn't a second-chance vest in this city that is going to protect you from a head shot."

All of which means the decoy is probably going to give up the car, Miller said, and the surveillance team will be obligated to pursue the thieves at high speed through city streets, putting the public further at risk.

Among Detroiters who wish the city would be more aggressive is Bruce Cross, 57, manager of the Concord Drugstore, where Ruth Wahl worked.

He remembers her as "a pretty young lady" with an "upbeat" attitude, a passion for volleyball and a penchant for "vibrant" fluorescent clothing. "When I kidded her about it, she used to say, `Well someone has to set the fashion statement here,' " Cross recalled.

He remembered, too, how thrilled "Ruthie" was when she got her new Suzuki, how she treated it like "her pride and joy" and parked it away from other cars to protect its finish from scratches and nicks.

Police say they have three men in custody in the Aug. 27 slaying of Ruth Wahl. Two were arrested almost immediately after a description of the brown station wagon was broadcast on the police scanner.

Another suspect was picked up a few days later after police traced the telephone number that flashed on a beeper worn by one of the two others.

Three guns were confiscated in connection with the arrests. The prosecutor assigned to the case said a preliminary ballistics analysis showed that one of the guns had been used to kill Wahl.

Police said that in a statement, the men said they had gone out that night looking for someone to rob. One of them had a debt to pay.

—The Philadelphia Inquirer, Oct. 2, 1991