The Justice Department announced on Tuesday that it had solved the largest cryptocurrency theft in history, confiscating a record $3.6 billion worth of bitcoin from a couple who allegedly hacked the Bitfinex cryptocurrency exchange in 2016.

Ilya Lichtenstein, 34, and his wife, Heather Morgan, 31, were arrested on Tuesday morning in New York's Manhattan. Liechtenstein and Morgan are behind the largest financial embezzlement in the history of the Justice Department, according to Lisa Monaco, US Deputy Attorney General. Monaco emphasized that the successful operation carried out by the Ministry of Justice was proof that cryptocurrency is no longer "a safe haven for criminals."

The Lichtensteins and Morgans, both New Yorkers, appeared in federal court in the Southern District on Tuesday afternoon. They were charged with conspiring to commit money laundering and defrauding the authorities. The case went to federal court in Washington, DC.

The couple is accused of laundering 119,754 bitcoins stolen from the Bitfinex cryptocurrency exchange hack. The Ministry of Justice officials said that at the time of the crime, the value of the stolen funds was estimated at $71 million in bitcoins, however, taking into account the growth in the value of cryptocurrency, now the volume of stolen bitcoins is estimated at more than $4.5 billion.

The key event in the investigation of this crime could be the collapse of the underground darknet market AlphaBay, which ceased to exist in 2017 as a result of law enforcement actions. The Ministry of Justice reported that part of the funds stolen by hackers was transferred to AlphaBay.

According to digital currency tracking firm Elliptic, the closure of the illegal site likely allowed authorities to access AlphaBay's internal transactions and link them to a cryptocurrency account held in Liechtenstein's name.

Bitfinex said in a statement that the exchange is working with the Department of Justice to establish our rights to recover stolen bitcoins.

Liechtenstein and his wife also tried to launder money through a network of money changers and wired the funds as payments to a start-up company started by Heather Morgan, the Justice Department said. On Tuesday, prosecutors said the illegal proceeds were used to buy everything from gold and NFC tokens to absolutely mundane Walmart gift certificates.