A senior level New York City housing official and six real estate developers were arrested and charged in a corruption probe, it was revealed by federal authorities in Brooklyn court Thursday.

All the defendants pleaded not guilty and were released on secured bonds.

Wendell Walters, an assistant commissioner with the Department of Housing Preservation and Development, was among those charged in the probe. Charges included bribery, extortion and money laundering.

Federal prosecutors allege that Walters accepted $600,000 in bribes from general contractors and a developer in exchange for lucrative city contracts to rehabilitate buildings and create affordable housing.

Walter's attorney, Howard Leader, said his client should be presumed innocent, but would not comment beyond that.

Walters, an HPD employee since 1998, has been suspended without pay, according to the department, the developers and contractors named in the investigation have been disqualified from doing work for the agency.

The contracts were worth $22 million and most involved projects in the Bronx and Brooklyn, prosecutors said.

The six real estate developers had been awarded HPD contracts and are accused of demanding kick-backs from the same contractors. The contractors cooperated in the investigation and were not indicted.  

Special Agent for the FBI, Michael Gaeta, said investigators were tipped off to the alleged corruption after indicting a contractor in 2008 for threatening a group of workers who had sued him.

"As it turned out that case, and as a result of individuals who we had spoken to, lead us towards this case," Gaeta said.