South Korean bitcoin exchange Youbit has ceased trading and announced it will file for bankruptcy after it was hacked for the second time this year.

The new hack occurred in the early morning of Dec. 19 local time and resulted in the loss of about 17 percent of total assets held by the exchange in its cryptocurrency wallets. A statement from the company did not say whether the theft exclusively involved bitcoin or included other cryptocurrencies. The previous hack, in April this year, saw approximately 4,000 bitcoins stolen.

The company, formally known as Yafi Co. Ltd., said it had immediately disabled trading and the ability of customers to withdraw funds to minimize further loses, with cryptocurrency assets held by customers to be marked down to 75 percent of their value once the company establishes a way for customers to withdraw funds in accordance with bankruptcy procedures.

Local police are only now starting their investigation into the new hack, but the previous one was attributed to North Korea, according to Reuters.

A report in September said the rogue state was found to have been intentionally targeting bitcoin exchanges in South Korea — albeit rather poorly, having only managed to steal 100 million won ($88,100) in bitcoin from 2013 to 2015 as part of an effort to increase the country’s hard currency. North Korea’s interest in bitcoin also extends to mining, with a report in July claiming that the country had started “state-sponsored bitcoin mining operations” on May 17.

The hack of Youbit may not be North Korea’s only successful major bitcoin heist this year. The country is also believed to have been involved in the hack and theft of bitcoin from South Korean exchange Bithumb July 5, though the exact amount stolen was never disclosed.

North Korea’s latest potential act of malfeasance comes a day after the country was accused by U.S. officials as being behind the WannaCry cyberattack this year that infected more than 300,000 computers worldwide and caused billions of dollars’ worth of damage.

Image: Youbit