Police in New Zealand confirmed they are investigating what appears to be a major hack of local cryptocurrency exchange Cryptopia worth at least $3.6 million, a press release stated on Jan. 16.

Cryptopia, which abruptly shut down its website and exchange services on Jan. 14, subsequently said it had detected malicious activity.

“The Cryptopia exchange suffered a security breach which resulted in significant losses,” officials wrote in a statement uploaded to the company’s Twitter account.

As users and the media learned of the hack, Cryptopia has since said it will not comment further on the ongoing proceedings as it is now in the hands of an official law enforcement investigation.

“We are unable to update anyone at the moment as it's now a police matter,” one of two similarly-worded tweets published earlier on Tuesday, Jan. 15 reads.

According to the police, the investigation is still at the stage of ascertaining the sequence of events.

“The inquiry is still in its very early stages and police are continuing to work with Cryptopia to establish what has happened and how,” the press release confirms, adding:

“Police are not yet in a position to say how much cryptocurrency is involved, other than it is a significant amount. A large team, including Canterbury CIB and specialist staff from the police High Tech Crime Unit, have been assigned to the case.”

The police note that they have a physical presence at the firm’s headquarters, but have not rushed the building, as had been misreported by local media. Cryptopia is fully cooperating with the investigation, the press release states.

In the aftermath of the reported breach, a lawsuit has been relaunched involving traders who claim they lost funds held on the exchange over a year ago.

According to local media and radio outlet Radio NZ, up to forty Cryptopia users have come forward to demand an explanation as to why their funds are inaccessible.

“We were contacted initially by about three people [last year], including a South African lawyer, who were complaining that they were having trouble transacting using their wallets and couldn't withdraw funds,” the lawyer handling the case told the publication.

Maintenance issues had been thought to be the cause of the problems.