"At 1:06 p.m., 342,000 Ethereum worth 58 billion won, were transferred from the Upbit Ethereum Hot Wallet to an unknown wallet," it said in a statement posted on the website of its exchange under the name of its CEO, Lee Seok-woo. "We took action right after detecting it."

The value of the lost cryptocurrency is expected to mark the largest in South Korea. Last year, Bithumb, the biggest cryptocurrency exchange in the country, lost some 35 billion won worth of coins in a hacking attack.

The loss will be compensated by Upbit's own reserves, the company said.

It also noted that all cryptocurrencies in its hot wallets have been transferred to cold wallets, which are safer because they are not connected to the internet. (Yonhap)