NEW ORLEANS — Former New Orleans Mayor Ray Nagin was indicted Friday on charges that he used his office for personal gain, accepting payoffs, free trips and gratuities from contractors while the city was struggling to recover from the devastation of Hurricane Katrina.

The charges against Nagin are the outgrowth of a City Hall corruption investigation that already has resulted in guilty pleas by two former city officials and two businessmen and a prison sentence for a former city vendor.

The federal indictment accuses Nagin of accepting more than $160,000 in bribes and truckloads of free granite for his family business in exchange for promoting the interests of a local businessman who secured millions of dollars in city contract work after the 2005 hurricane. The businessman, Frank Fradella, pleaded guilty in June to conspiracy to commit bribery and has been cooperating with federal authorities.

Nagin, 56, also is charged with accepting at least $60,000 in payoffs from another businessman, Rodney Williams, for his help in securing city contracts for architectural, engineering and management services work. Williams, who was president of Three Fold Consultants LLC, pleaded guilty Dec. 5 to a conspiracy charge.

The indictment also accuses Nagin — who now lives in Frisco, Texas — of getting free private jet and limousine services to New York from an unidentified businessman who owns a New Orleans movie theater. Nagin is accused of agreeing to waive tax penalties that the businessman owed to the city on a delinquent tax bill in 2006.

From several city contractors, Nagin is accused of accepting free travel and vacation expenses for trips to Hawaii, Chicago, Las Vegas and Jamaica while in office.

The alleged bribery plot isn't limited to Nagin's tenure as mayor. Prosecutors say Nagin, a Democrat, accepted monthly payoffs from Fradella totaling $112,250 after he left office.

In 2010, Greg Meffert, a former technology official and deputy mayor under Nagin, pleaded guilty to charges he took bribes and kickbacks in exchange for steering city contracts to businessman Mark St. Pierre. Anthony Jones, who served as the city's chief technology officer in Nagin's administration, also pleaded guilty to taking payoffs.

Meffert cooperated with the government in its case against St. Pierre, who was convicted in May 2011 of charges that include conspiracy, bribery and money laundering. The indictment says Nagin accepted bribes from St. Pierre, including free travel and lodging, cell phone service for relatives, and campaign funding.

Nagin, a former cable television executive, was a political novice before being elected to his first term as mayor in 2002, buoyed by strong support from white voters. He cast himself a reform-minded progressive who wasn't bound by party affiliations, as he snubbed fellow Democrat Kathleen Blanco and endorsed Republican Bobby Jindal's unsuccessful gubernatorial campaign in 2003.

Katrina elevated Nagin to the national stage, where he gained a reputation for colorful and sometimes cringe-inducing rhetoric.

During a radio interview broadcast in the storm's early aftermath, he angrily pleaded with federal officials to "get every doggone Greyhound bus line in the country and get their asses moving to New Orleans." In January 2006, he apologized for a Martin Luther King Day speech in which he predicted New Orleans would be a "chocolate city" and asserted that "God was mad at America."

Strong support from black voters helped Nagin win re-election in 2006 despite widespread criticism of his post-Katrina leadership. But the glacial pace of rebuilding, a surge in violent crime and the budding City Hall corruption investigation chipped away at Nagin's popularity during his second term.

Nagin could not seek a third consecutive term because of term limits. Mitch Landrieu, who ran against Nagin in 2006, succeeded him in 2010.

Aaron Bennett, a businessman awaiting sentencing in a separate bribery case, told The Times-Picayune that he introduced Nagin to Fradella specifically to help the mayor get Home Depot granite installation work for a business that he and his sons founded. Fradella's company received more than $4 million in city contracts for repair work at Louis Armstrong New Orleans International Airport and in the French Quarter after Katrina, the indictment says.

Some of the allegations in the indictment have been the subject of state ethics complaints.

In April 2010, the Louisiana Board of Ethics charged Nagin with two possible violations of state ethics law. One charge involved Nagin's "use of a credit card and/or gifts" from St. Pierre. In the other charge, the Ethics Board said Stone Age LLC, the Nagin family's business, was compensated for installation services provided to Home Depot while the home improvement retailer was negotiating tax breaks from the city.

The indictment doesn't mention Home Depot by name but says Nagin approved a 2007 ordinance that allowed city property to be sold to an unidentified "major retail corporation" at the same time he was soliciting the retailer for work for his granite business.

Nagin has largely steered clear of the political arena since he left office. On his Twitter account, he describes his current occupations as author, public speaker and "green energy entrepreneur." He wrote a self-published memoir called "Katrina's Secrets: Storms After the Storm."

A few hours before his indictment, Nagin retweeted a post by Texas megachurch pastor Joel Osteen that says, "You are closest to your victory when you face the greatest opposition."

Nagin's attorney, Robert Jenkins, didn't immediately return cellphone calls seeking comment on the indictment.

Landrieu, Nagin's successor, said it was a "sad day" for the city.

"Today's indictment of former Mayor Ray Nagin alleges serious violations of the public's trust," he said in a statement. "Public corruption cannot and will not be tolerated."

Nagin's indictment is another blemish on the reputation of the city, which has been plagued by decades of corruption.

"I was really disappointed in him," said Norlita Parker Wells, a city employee. "I expected more from him. I think it's funny only because when he was entering office he said he was going to run such a tight ship. What happened?"