NEW YORK CITY ? Eight members and associates of the Gambino organized crime family, including an acting underboss, have pleaded guilty to racketeering charges, authorities said Friday.

The eight were among 11 people charged with racketeering in a prosecution aimed at taking down current and future leaders of a crime family more than a century old.

The arrests stemmed from a probe in which an undercover FBI agent infiltrated the mob during a three-year period with an act so convincing he was considered for membership, authorities said.

The eight agreed to forfeit a total of about $550,000 for their roles in a decadelong racketeering scheme including assaults, extortion, loansharking, union embezzlement, illegal gambling, trafficking in stolen property and fraud.