106 New York City police officers, firefighters and prison guards were arrested for allegedly taking part in a $400 million Social Security scam, one of the largest in history.

Dozens of retired NYC workers were charged Tuesday with falsely reporting psychiatric problems in order to get federal disability benefits. Some even claimed that their fake psychiatric conditions were a result of 9/11 post-traumatic stress.

Among the retirees arrested included 72 city police officers, eight firefighters, five correction officers and one Nassau County Police Department officer.  All were wrongly receiving thousands of dollars in federal disability benefits, prosecutors said Tuesday while announcing the sweeping fraud case, the AP reports.

Investigators said the scam dates back to more than 20 years ago when the ex-officers and workers began collecting benefits by citing bogus mental health problems. The workers were coached on how to portray their problems and convincingly report that they were too psychologically damaged to take care of themselves, prosecutors said.

Many of them claimed they couldn't sleep, leave their home or use a computer. However, they were busted after investigators found evidence that they had been piloting helicopters, riding Jet Skis, teaching karate, running in half-marathons and managing social media accounts

One retired police officer who claimed to be unable to work due to psychological damage taught martial arts, prosecutors said. Another claimed that he was house-bound due to his depression, but was photographed on a watercraft. In addition, an ex-cop claimed to be incapable of social interactions, however he worked at a cannoli stand during a street festival.

"The brazenness is shocking," said Manhattan District Attorney Cyrus R. Vance Jr. 

"That's about as inconsistent with being disabled and unable to perform physical or mental chores as you can get,'' he added, reports the New York Post.

Four ringleaders, including an 81-year-old ex-FBI agent and an 89-year-old pension adviser, coached the former workers on how to pocket up to $50,000 a year in bogus claims. In return, the ringleaders made tens of thousands in dollars in secret kickbacks, said Vance Jr.

Many of the officers legitimately had physical disabilities that would have entitled them to state disability pensions, but would not have entitled them to federal Social Security disability insurance, which requires a complete inability to work, according to MSN.

Arraignments in the sweeping case began Tuesday, with several of the defendants pleading not guilty and being released without bail.