TRENTON, N.J. (CBSNewYork/AP) — Federal agents arrested the mayor of Trenton early Monday as part of an ongoing corruption investigation. They’d been looking into bribery allegations related to a parking garage project that was concocted as part of an FBI sting operation.

Mayor Tony Mack was taken to an FBI office in Hamilton for processing.  He has since been released from federal custody on $150,000 bond.

EXTRA: Mack’s Criminal Complaint | Giorgianni’s Criminal Complaint

Mack said nothing as he left the federal courthouse in Trenton on Monday afternoon. His attorney also declined to comment on the case brought against Mack in an FBI sting operation.

1010 WINS’ Steve Sandberg reports

Mack, his brother, Ralphiel, and convicted sex offender Joseph Giorgianni, are accused of conspiring to obstruct, delay and affect interstate commerce by extortion under color of official right.

Federal prosecutors alleged Mack agreed to use his influence in connection with a proposed parking garage project in the city. The garage was made up — a fake project created by investigators to try to capture Mack, who has financial problems and attracted legal scrutiny since he took office.

U.S. Attorney Paul Fishman said at a news conference Monday that the city-owned land for the garage was assessed at $271,000. He said Mack and Giorgianni agreed to accept $100,000 for the land for the city coffers as long as the purported developers paid a bribe of $100,000 to be split between the two alleged conspirators.

“The complaint charges that Mayor Mack and his co-conspirators were willing to let the city property go for a fraction of its value and he allegedly chose as his middle man a convicted felon who was simultaneously heading a conspiracy to traffic in prescription medication,” Fishman said.

Federal agents began working with an informant to gather information on Mack and the others in September 2010, just two months after Mack took office. Fishman would not say when the investigation began or why.

The defendants received $54,000 and anticipated accepting another $65,000 from a cooperating witness who purported to be a developer, according to court documents that laid out the sting and the accusations of wrongdoing.

The complaint also said that $2,500 in $100 bills with the serial numbers of those given to Giorgianni were found in a search of Ralphiel Mack’s home in July.

“The mayor went to great lengths to insulate himself using a convicted felon as his alleged bagman and his brother as the middle man who handled the money,” the FBI Special Agent in Charge Michael Ward.

Mack’s administration has been in turmoil from Day 1, staggering from one crisis to another. A housecleaning of staff at City Hall opened the door for Mack’s own appointees, who quickly turned it into a revolving door.

Under an agreement reached last year, the Democrat can hire department heads only from a pool of applicants the state offers or he risks losing $6 million in state aid.

One of his early backers was Giorgianni. The businessman went to prison in the 1980s on charges of carnally abusing and debauching the morals of a 14-year-old girl in the back of his sandwich shop.

The case gained notoriety because of weight-related health problems that got Giorgianni, a steakhouse owner who once claimed to tip the scale at over 500 pounds, released and led a prosecutor to charge he “ate his way out of jail.”

Giorgianni was also charged Monday with conspiracy to distribute oxycodone pills in the Trenton area in a separate complaint along with eight other defendants.

He faces up to 50 years in prison if he’s convicted on all charges.

The mayor and his brother could each face 20 years in prison if convicted.

(TM and Copyright 2012 CBS Radio Inc. and its relevant subsidiaries. CBS RADIO and EYE Logo TM and Copyright 2012 CBS Broadcasting Inc. Used under license. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed. The Associated Press contributed to this report.)

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