A North Korean government-backed hacking group penetrated an American IT management company and used it as a springboard to target cryptocurrency companies, the firm and cybersecurity experts said on Thursday.

The hackers broke into Louisville, Colorado-based JumpCloud in late June and used their access to the company’s systems to target "fewer than 5" of its clients, it said in a blog post.

JumpCloud did not identify the customers affected, but cybersecurity firms CrowdStrike Holdings — which is assisting JumpCloud — and Alphabet-owned Mandiant — which is assisting one of JumpCloud's clients — both said the hackers involved were known to focus on cryptocurrency theft.