A U.S. cryptocurrency investor on Thursday sued a suburban New York high school senior, accusing the 18-year-old of being the mastermind and ringleader of a cybercrime scheme that defrauded him out of millions of dollars in digital currencies.

The plaintiff, Michael Terpin, accused Ellis Pinsky, of Irvington, New York, and his alleged co-conspirators of stealing $23.8 million of cryptocurrency in January 2018, when the defendant was 15, and is seeking triple damages of $71.4 million.

“On the surface, Pinsky is an ‘All American Boy,'” Terpin said in a complaint filed in federal court in White Plains, New York. “The tables are now turned.”

Pinsky could not immediately be reached for comment. Calls to a phone number for him obtained through court records and a public records search were not answered. It was unclear whether Pinsky has a lawyer.

Cryptocurrency crime is a growing problem, with losses soaring to $4.52 billion last year from $1.74 billion in 2018, according to cybersecurity company CipherTrace.

In his complaint, Terpin said Pinsky and his “gang of digital bandits” would steal from victims after gaining control of their smartphones through “SIM swaps,” and that Pinsky bragged to friends that he would never get caught.

Terpin accused Pinsky and his alleged co-conspirators, none identified by name in the complaint, of violating federal laws against racketeering and computer fraud.

Terpin in May 2019 won a $75.8 million civil judgment in a related case in a California state court against Nicholas Truglia, an alleged Pinsky associate who has faced criminal hacking charges in California and New York.

Terpin said the New York charges relate to the $23.8 million theft. Terpin is also suing his carrier AT&T Mobility in Los Angeles for $240 million, court records show. A judge is considering AT&T’s bid to dismiss that case, the records show.

SIM swapping occurs when a hacker tricks a mobile phone carrier into transferring a target’s phone number from a registered SIM card, the small plastic chip connecting a phone to a cellular network, to a SIM card he or she possesses. This can be done with help from someone at the carrier, or by stating information about the target obtained from social media and other accounts.