A prolific hacker who has stolen hundreds of millions of user records from a variety of websites has struck again. The Coinmania cryptocurrency exchange said it was one of the victims of the latest hack of user information.

According to a recent Reddit post, Coinmama officials learned that about 450,000 emails and hashed passwords were stolen after a breach. Initial suspicion is that no other parts of the Coinmama system were compromised due to the “dated nature of the published data.”

A post on Coinmama’s website said the passwords and emails were posted onto a dark web registry. Information, according to Coinmama, pertained to users who registered up until August 5th, 2017.

The individual behind the hack has gained notoriety due to the scope and breadth of stolen user records they have managed to acquire. They previously stole and put 620 million user records for sale after managing to steal the information from 16 different companies.

Reporting from Zdnet said the hacker ‘Gnosticplayers’ put up a new batch of 127 million stolen user records for sale from eight different companies, including Coinmama. Stolen accounts in the second batch came from file sharing service Ge.tt, travel booking company Ixigo, gaming company Roll20.net, and pet food delivery service Petflow, along with some other entities.

Zdnet said at the time of publication, the databases from the original 16 companies were not available for sale. Gnosticplayers said they took down the batch after people said a long sale would eventually lead to the databases becoming leaked online.

On its website, Coinmama advised all users to change their password if they registered before August 5th, 2017. It also cautioned people about downloading attachments from suspicious emails and issued a reminder to users to create complex passwords that are unique.

Recently, the New Zealand police force indicated it has been making progress on the Cryptopia exchange hack. Detective inspector Greg Murton said the stolen cryptocurrency is being tracked on an international scale. He also said authorities are working with Cryptopia executives to hunt down the criminals.

However, the investigation will most likely take a lot of time due to the complex nature of the case. Many are skeptical that the criminals will actually face arrest because of the nature of the hack. However, police have said investigations at the Cryptopia headquarters are set to wrap up soon.