In a news conference on Thursday, Burlington County Prosecutor Scott Coffina said the tale was "fictitious" and "formed the basis of a scam."
Coffina said it was, "concocted to compel kind-hearted individuals to contribute to the cause."
"The entire campaign was predicated on a lie," said Coffina.
It all began in November, 2017, when 28-year-old Kate McClure claimed that 35-year-old Johnny Bobbitt helped her out by using his last $20 to buy gas after she became stranded along I-95 in Philadelphia.
Claiming they wanted to "pay it forward," McClure and her boyfriend, 39-year-old Mark D'Amico launched a GoFundMe campaign with the goal of raising $10,000 to help Bobbitt get back on his feet.
They went on a media blitz to promote the campaign, and it ultimately raised about $400,000.
However, Coffina said, investigators learned McClure texted a friend less than an hour after the campaign went live saying the story was "completely made up." She did not run out of gas, Coffina said, and Bobbitt did not spend $20 to help her.
McClure, D'Amico and Bobbitt conspired to fabricate and promote the "feel-good" story with the hopes of raising additional funds, Coffina said.
All three have been charged with Theft by Deception (second-degree,) and Conspiracy to Commit Theft by Deception (second-degree).
D'Amico and McClure, both of Florence Township, New Jersey, surrendered on Wednesday night. They were processed and released.
Bobbitt, of the Kensington section of Philadelphia, was charged on Wednesday and is awaiting extradition.
Coffina said GoFundMe has cooperated with the investigation, and will be refunding all of the donations.