Former New Orleans Mayor Ray Nagin pleaded not guilty Wednesday to charges that he accepted more than $200,000 in bribes plus free trips and other gratuities in exchange for helping contractors secure millions of dollars in work for the city.

U.S. Magistrate Sally Shushan set Nagin’s bond at $100,000 during his arraignment on charges that included bribery, wire fraud and filing false tax returns. She also set a preliminary trial date of April 29.

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

Nagin’s arraignment marked a rare public appearance for Nagin, who now lives in Frisco, Texas, and has kept a low profile since he left office in 2010.

Nagin was a political novice before he was first elected mayor in 2002, but Hurricane Katrina turned him into a national figure with a reputation for cringe-inducing rhetoric. His popularity steadily waned in the aftermath of the 2005 storm, as the city struggled to recover from the epic flooding unleashed by broken levees.

A 21-count indictment last month accused Nagin, 56, of accepting more than $160,000 in bribes and truckloads of free granite for his family business in exchange for promoting the interests of Frank Fradella, a local businessman. Fradella pleaded guilty in June to conspiracy to commit bribery and has been cooperating with federal authorities.

Nagin is also 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 pleaded guilty in December to a conspiracy charge.

The indictment also accused Nagin of getting free private jet and limousine services to New York from an unidentified businessman who owned 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.

Greg Meffert, a former technology official and deputy mayor under Nagin, pleaded guilty in 2010 to taking 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.

St. Pierre was convicted in May 2011 of charges that included conspiracy, bribery and money laundering. Nagin’s indictment accused him of accepting bribes from St. Pierre.

Nagin served two terms as mayor. Term limits prevented him from seeking a third.