The New Jersey couple who raised hundreds of thousands of dollars in a viral charity campaign for a homeless man were allegedly working with the vagrant as part of an elaborate ruse, according to a new report.

Prosecutors believe that Mark D’Amico and Kate McClure conspired with homeless man Johnny Bobbitt to create their get-rich-quick scheme in 2017, NBC’s Philadelphia affiliate reported.

The New York Post reports that the couple turned themselves in to authorities overnight, but Bobbitt was still at large.

According to a source who spoke to the news outlet, which said it had a copy of a criminal complaint, all three are expected to face charges of conspiracy and theft by deception for working together to create the ruse.

Prosecutors did not immediately return a call for comment, and reps for the couple and Bobbitt were not available.

McClure, 28, and D’Amico, 39, created a GoFundMe page in November 2017, claiming the homeless, drug addict Bobbitt spent his last $20 to fill up McClure’s empty gas tank after her car broke down near Philadelphia.

The charity campaign exploded, raising tens of thousands of dollars from unsuspecting donors in a matter of days — and ultimately shooting up to more than $US400,000 ($A550,000).

“It has changed my entire outlook about people, my outlook about people has skyrocketed,” McClure said of the donations at the time.

Their plan began to unravel in August of this year, when Bobbitt sued the couple, claiming they were withholding funds raised on the GoFundMe from him.

McClure and D’Amico, both of Florence Township, New Jersey, accused Bobbitt of being on drugs and refused to pay him until he was clean.

In September, a lawyer for the couple announced that he expected they would both be indicted for their role in the scam — but it was not known that all three of them were suspected in the plot until now.