GREENBURGH, N.Y. (CBS) ― Drive around New York City or the suburbs and there’s a good chance your car will be captured on a “not-so-candid” camera.

A growing number of police departments are using high-tech license plate readers to keep an electronic eye on drivers.

It’s the sound that says big brother is watching.

Each beep signifies a license plate scanned by the cameras mounted on the back of a Greenburgh police car and checked against a database on the laptop computer up front.

“We get suspended registrations, stolen vehicles, warrants,” Officer Eric Lederer said.

Lederer said the license plate reader — or “LPR” — has dramatically boosted his effectiveness on patrol.

CBS 2 HD was riding along for just a few minutes when the LPR alerted Lederer to a vehicle with $500 in unpaid parking tickets.

“We’ll call a tow truck and have the car impounded,” Officer Lederer said.

The license plate readers are so blazingly fast — in just the brief time CBS 2 is on camera the LPR camera can scan and check more than 400 license plates.

The NYPD started with 12 LPRs in 2006. Today it has more than 100, including stationary units that collect license plate data and feed it to the Department’s anti-terror command post.

The Greenburgh patrol captain said LPRs have tremendous crime-fighting and anti-terror potential.

“If there’s a problem in the area, we can go back the next day, few hours later and see what cars were in the area. If there’s a particular car we’re looking for we can varify if it was in the area or not,” Capt. Glenn Bryan said.

Some residents have privacy concerns.

“I think it’s a little creepy, a little too much invasive of privacy,” one person said.

“If I’m not breaking the law, I have nothing to worry about,” another added.

Regardless, area police departments plan to expand their network of electronic eyes on the road.

Many departments are using homeland security grant money to purchase license plate readers. A unit on a patrol car can cost $15,000.

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