Hackers of cryptocurrency platforms stole around $1.7 billion in 2023, around 54.3% lower than the year before, a Chainalysis report showed Wednesday.

Cyber attacks have been a persistent challenge for the crypto industry, and widespread hacking is one of the reasons why most regulators around the world frown upon crypto.

Though stolen funds more than halved, the number of individual hacking incidents grew to 231 last year from 219 in 2022, Chainalysis said.

The number of hacks by North Korea-linked organizations rose to 20 last year, the highest on record. They stole slightly over $1 billion, Chainalysis estimated, compared with $1.7 billion in 2022.

North Korea has previously denied allegations of hacking or other cyber attacks.