A U.K. man, Lewys Martin, pleaded guilty in London last week to blackmail, possession of articles for use in fraud and possession of indecent images of children, a report from a Bitcoin news site CoinTelegraph.com revealed.

The 22-year-old was linked to previous claims by Lloyd’s Banking Group, which reported that it was blackmailed by an attacker that had accessed the bank account details of 28,000 customers, the news site said. The bank reported Martin in May 2013, after he threatened to sell the information to criminals, if he was not paid via Bitcoin.

According to CrimeandJustice.co.uk, indecent photos of children, not related to the blackmail investigation, were found after police seized Martin’s computer and phone.

Martin is scheduled to be sentenced next month in Southwark Crown Court in London.