Image caption Manhattan District Attorney Cyrus Vance labelled the alleged disability fraud "shocking" (file photo)

Dozens of US former emergency service workers have been arrested in a sweeping fraud investigation involving federal disability benefits, New York authorities say.

Prosecutors say 72 police officers, eight firefighters and five corrections officers are among those charged.

Some reportedly falsely claimed disabling conditions arising from the 11 September 2001 attacks.

The fraud is believed to have cost hundreds of millions of dollars.

"The brazenness is shocking," Manhattan District Attorney Cyrus Vance said on Tuesday.

"Many participants cynically manufactured claims of mental illness as a result of September 11, dishonouring the first responders who did serve their city at the expense of their own health and safety," he added.

Incriminating photos

Four men, including a retired police officer and a disability consultant with a New York detective's union, appeared in court on Tuesday on grand larceny charges.

The defendants, allegedly the ringleaders of the fraud operation, were released on bail of up to $1m (£609,690).

Those men stand accused of coaching the former emergency workers on how to feign mental health problems and fail memory tests in an effort to draw disability benefits, collecting tens of thousands of dollars in kickbacks.

One retired police officer told doctors he suffered panic attacks and was unable to leave his house - only to post photographs of himself on social media riding a jet ski.

Another retired policeman collected a disability pension for a neck injury - and then went on to open a martial arts studio

Yet another, who claimed he was incapable of social interaction, was found to be running a cannoli stand at a street festival.