Federal prosecutors charged 70 current and former employees of the New York City Housing Authority, the largest public housing agency in North America, on Tuesday with taking bribes in exchange for awarding no-bid contracts.

Damian Williams, the U.S. attorney in Manhattan, called it “the largest single-day bribery takedown” in the history of the U.S. Department of Justice.

The current and former NYCHA employees, 66 of whom were arrested on Tuesday morning, according to Williams’ office, are each charged with extortion as government workers, which carries a maximum sentence of 20 years in prison, and with soliciting and receiving bribes. Some of the accused also face additional conspiracy charges.