During the last four weeks, Big Brother in Camden has taken note of 624 vehicles whose occupants did something suspicious near one of the city's busiest open-air drug markets, Sixth and York Streets.

The owners of these vehicles will receive letters next week warning them that their vehicles were seen - by the city's Eye in the Sky surveillance network - in the high-crime and drug-trafficking area.

"Not only has your vehicle and tag number been recorded, appropriate criminal and/or traffic offenses may be charged if our investigation reveals your vehicle and occupants to be involved in illegal activity," the letter reads.

The Camden County Prosecutor's Office and the Camden Police Department, both of which faced deep personnel cuts last year, hope the initiative will serve as a deterrent to drug buyers in a city long plagued by drug-related crimes.

The project has confirmed what city officials have been hearing from residents for a long time: Camden's drug and crime issues are not insulated city problems. Out of the 624 letters going out (205 are repeat offenders), 90 percent are going to residents of suburban communities, Cherry Hill and Sewell being the most common destinations.

"It's really a regional public safety issue," said Camden Mayor Dana L. Redd. "I think we're getting the truth now as to what's happening in our city."

However, civil liberties advocates and experts expressed concern about the unintended consequences of police targeting cars that are only seen to stop in an area of high crime.

The list of vehicles from the camera initiative "can be easily abused," said David Rudovsky, a Philadelphia civil rights and criminal defense lawyer. "People become targets unfairly just because a car was seen at the wrong place at the wrong time."

But police say the vehicles targeted in the letters - and watched on monitors by veteran officers - are those which a police officer would have normally stopped and questioned for suspicious behavior had the officer been stationed at that corner.

"It's occupants engaging in activity that is consistent with drug trafficking," Police Chief Scott Thomson said about people illegally parking and going into an alley for at most a few minutes.

"That's not abuse, it's good police work," he said.

Video surveillance from the $1.8 million camera system, installed last year, has been capturing people of all ages and socio-economic backgrounds coming into Camden to buy heroin, crack, and marijuana, officials said.

The Police Department, which has yet to recover its full strength following massive layoffs early last year, is too short-staffed to be breaking up the dozens of drug corners at all hours, Thomson said.

The 81 surveillance cameras throughout the city "broadened the scope of our coverage," he said. Forty more are scheduled to be installed within weeks. The chief would not disclose the locations of the new cameras.

Those hustling on the corner in North Camden, mostly 20-somethings who have grown up in the drug-infested environment, say the cameras have not deterred them.

"I smile at it every day," said one young man, who declined to give his name, while waving and smiling at the camera above him at Fourth Street and York. "There's nothing they can do about it."

A drive through North Camden in the morning proves that the drug trade is still open and thriving. Almost every corner has one or two dealers eager to sell to the prework crowd.

While driving into work, County Prosecutor Warren Faulk says he notices that so many cars make a right on Seventh Street to head into North Camden.

"Sometimes I follow them. . . . There's no reason for someone from Cherry Hill to be going into North Camden at 8 a.m.," Faulk said.

Only after five years of no suspicious activity is a tag number erased from Camden's system, Thomson said, and there is no appeal process for challenging a surveillance letter.

Camden is also sending the information to the motorists' local police departments so they, too, can be on the lookout for those vehicles, Faulk said.

"If in fact they are coming into the city to buy drugs, they could also be responsible for burglaries or break-ins [in their towns] to keep up their drug habit," Faulk said.

Edward Barocas, legal director of the American Civil Liberties Union of New Jersey, said that while many cities have surveillance cameras, he had never heard of any other municipality writing to vehicle owners about their presence in high-crime areas.

"I find it extremely troubling," Barocas said after reviewing a draft of the letter.

"It is done in such a heavy-handed way. . . . People have the right to visit their family member or doctor even if they are located in a high-crime area," he said.

A spokesman for the Philadelphia police said the letter campaign is a good strategy.

"If you are using Mom and Dad's car and saying you're going to the mall when really you are going to Camden to buy crack then, yeah," said Lt. Ray Evers, "It's a good tactic." He added that many of those letters will likely prompt parental intervention.

But, Evers said, he does not expect Philadelphia to follow suit soon. While there are 240 surveillance cameras throughout the city, the department first has to fix the more than 100 cameras that are out.