A driver for Fairfield Cab has been charged with buying liquor for big-tipping 15-year-old passengers at a Fairfield Beach liquor store Tuesday evening.

The problems for cabbie Joseph Sistrunk, 55, of Fairfield Avenue in Bridgeport, started after he picked up four teens outside the Greenfield Mercato on Bronson Road around 7 p.m., police said.

Two off-duty Fairfield police officers saw Sistrunk go to That's The Spirit liquor store on Fairfield Beach Road, then leave with several packages -- 12-packs of beer -- and turn them over to the teen passengers in the cab.

The teens got out of the cab and the cabbie left the scene, but was stopped by police at Sasco Hill and Post roads a short time later.

Sistrunk was charged with illegal delivery of liquor to a minor and risk of injury to a minor. He was released on a promise to appear July 19 in Bridgeport Superior Court.

Three of the 15-year-olds -- one from Fairfield, one from Westport and the third from New Canaan -- were each charged with possession of alcohol by a minor. A fourth was not charged because he did not have any beer in his possession at the time of his friends' arrest.

According to the police report, the group gave the driver $30 for the $9 trip.