NORTH ANDOVER - Police said an 18-year-old man stole a BMW he found unlocked with the keys in it and then drove around town breaking into 25 other cars and stealing loose change, cell phones, personal stereos and other property.

All of the cars were in the East Water, Pleasant Street and Elm Street neighborhoods, and all had been left unlocked by their owners, police said.

Lt. John Carney, operations commander for the Police Department, said police caught a break when the accused thief entered the car of an off-duty police officer, who was able to see him drive away in the BMW and notified other officers who were already in the area checking reports that some cars had been entered.

After a short chase, the stolen BMW was pulled over at Elm Street and Elmcrest Road at 1:45 a.m.

The lone occupant of the car, David Davis, of 27 E. Water St., Apt. 18, was charged with 25 counts of breaking and entering a motor vehicle in the nighttime with intent to commit a felony, larceny of a motor vehicle, driving while under the influence of alcohol and driving while under the influence of drugs, including cocaine, Klonopin and Liquid G, which police said is a date rape drug.

Carney said under Massachusetts law, a car does not have to be locked for someone to be charged with breaking into it.

Davis also was charged with failure to stop for a police officer, driving without a license, and driving after suspension of his license.

The term Liquid G is street slang for GHB, or gamma hydroxybutyrate which is abused for its euphoric, sedative or anabolic (body building) effects, according to a Web site called Recovery Lane, which is aimed at helping addicts recover.

Carney said Davis was no stranger to the officers who arrested him.

"The same officers arrested him on Jan. 13 and charged him with driving while under the influence of alcohol and larceny of a motor vehicle, after he took a box truck belonging to his employer and drove it into a building. His license was suspended as a result of that incident," Carney said.

Carney said Davis was taking so much property he placed it in a bag that he probably got from one of the cars.

He also put his wallet and personal identification into the bag with the stolen property then left the bag at the scene of one of the car breaks at 25 Pleasant St., Carney said.

"He took off and left it there. I don't know if he got spooked or what," Carney said.

Coincidentally, Davis was supposed to appear in Lawrence District Court yesterday for a pretrial conference on the charges stemming from the January arrest, Carney said.