SEOUL: North Korea appears to be diversifying its cybercrimes to offset the declining value of cryptocurrencies it steals to fund its nuclear and missile programmes.

According to the report by Kim Bomi, a research fellow at the Institute for National Security Strategy, North Korea stole some $340 million worth of cryptocurrencies in the first three quarters of the year, which amounts to 29.6 per cent of the total damage reported in the world, but is still less than the unprecedented volume it stole last year.

Bomi attributed the decline to the sharp drop in the value of cryptocurrencies amid US interest rate hikes and the bankruptcy of cryptocurrency exchange operator FTX, reports Yonhap News Agency.

Bomi also cited countries' strengthened monitoring and sanctions in the wake of last year's hacking of Axie Infinity, a token-based online video game, by North Korean state-sponsored hacking group Lazarus, which led to the theft of $620 million worth of cryptocurrencies.

"North Korea is renewing its interest in attacking the financial sector," Bomi wrote.

"Starting last year, ransomware attacks are also on the rise."

Bomi also said North Korea appears to be relying on Russian exchanges to cash its cryptocurrencies.