New York (CNN) -- New York prosecutors Tuesday announced the indictments of an additional 32 people in a multimillion-dollar Social Security fraud scheme that involved retired cops and firefighters who falsely claimed to have suffered from post-traumatic stress disorder after the 9/11 terrorist attacks.
"Dozens of additional defendants have been charged with fabricating psychiatric conditions in order to fraudulently obtain Social Security disability insurance, a critically important social safety net reserved for those truly in need," Manhattan District Attorney Cyrus Vance, Jr., said in a statement. "These defendants are accused of gaming the system by lying about their lifestyle, including their ability to work, drive, handle money, shop, and socialize, in order to obtain benefits to which they were not entitled."
The scandal first broke in January when the Manhattan prosecutors, the U.S. Department of Homeland Security Investigations and New York police announced the indictments of 106 people, including many retired police and firefighters, for allegedly scamming the Social Security system by collecting insurance payments when they weren't fully disabled.
Of the 32 newly indicted defendants, at least six had pleaded not guilty Tuesday afternoon while others were expected to appear in court later.
Sixteen of the new defendants were also collecting pension as retirees of the New York City Police Department, four from the New York City Fire Department, one from both the NYPD and FDNY, and one from the Department of Corrections, prosecutors said.
All the defendants previously arrested in the case have pleaded not guilty.
Prosecutors have said in their cases that more than half the defendants received funds for fraudulent claims of post-traumatic stress disorder in the wake of the September terror attacks on the World Trade Center.
The alleged scam spanned more than two decades, with law enforcement officers and firefighters coached on how to behave during doctor visits to qualify for full disability benefits, officials said.
The defendants received up to $50,000 a year because, they claimed, they were no longer able to work, officials said. Many of the claims allegedly involved work-related trauma caused by the 9/11 terror attacks. The 9/11-related claims alone totaled hundreds of thousands of dollars.
Prosecutors said four men at the center of the case directed and coached hundreds of Social Security Disability Insurance applicants, including many retirees of the New York police and fire departments, to lie about psychiatric conditions in order to obtain benefits.
Prosecutors said the defendants were meticulously instructed on how to fail memory tests with plausibility, how to dress and how to behave. Nearly every application included identical descriptions of daily living.
The leaders of the scheme allegedly collected one-time cash payments based on the monthly disability awards, ranging from approximately $20,000 to $50,000, prosecutors said.
Some of those charged had gone on to hold other jobs, even though the full disability they received involved a diagnosis that they were so traumatized they were incapable of performing any kind of work, officials added.
In some instances, prosecutors said, the total amount fraudulently obtained was nearly $500,000 per applicant. The average Social Security disability Insurance payment to date for the defendants, which included retroactive lump sum payments, was about $210,000.
CNN's Elizabeth Landers and Lorenzo Ferrigno contributed to this story.