The two recent cases are unusual because scammers are often able to stay out of reach of American law enforcement since they are based abroad, often in West Africa, said Patrick Peterson, chief executive of Agari, a cybersecurity firm that tracks internet fraud.
“What makes this very unique,” he said, “is Mr. Sarpong lives in New Jersey, and his co-conspirators are still safe and sound in Ghana, with hundreds of thousands of dollars in proceeds.”
Mr. Peterson said the two cases suggested that American authorities were trying to do more to combat such romance frauds, which data shows are increasing. The F.B.I. said it received nearly 18,500 complaints from victims of romance or similar internet frauds last year, with reported losses exceeding $362 million, up 71 percent from 2017.
Law enforcement is “starting to crack the code on how to do this repeatedly and at scale, and they’re trying to invest more because the losses are so high,” Mr. Peterson said.
In New Jersey, the fake relationships moved fast and did not last long. Many had similar themes: an introduction through a dating website; a soldier overseas; gold bars worth millions; and a few pesky bills to be paid before both the suitor, and treasure, could materialize.
The fraud started in January 2016, officials said. That’s when a woman said she began talking with a man claiming to be a petty officer in the United States Navy, stationed in Canada. He asked the woman to send him $3,000. She later told authorities she wound up losing about $50,000.
In November 2016, another victim was contacted. Over the course of four months, this person sent nearly $200,000 to a man who said he was in the military and needed help getting “approximately $10 million dollars in gold bars and cash out of Syria,” according to the complaint. The impostor spoke to the victim through the dating website Plenty of Fish, and Google Hangouts.