North Korean hackers have targeted at least six companies in the US, UK and South Korea working on coronavirus treatments since August, Dow Jones reports, citing unidentified people familiar with the matter.

Targets include Johnson & Johnson and Novavax, as well as three South Korean companies, namely Genexine Inc, Shin Poong Pharmaceutical, and Celltrion.

Hackers also targeted AstraZeneca, a development which Reuters first reported Friday.

It was not known if North Korean hackers succeeded in getting useful information. North Korea has coordinated attacks on the six companies since August, the people told Dow Jones.

Shin Poong and Celltrion said they received hacking attacks but didn’t detect damage, spokesmen told DJ.

A J&J spokesman told DJ the company remains vigilant against its data, while a Novavax spokeswoman said the company is aware of foreign threats.

Genexine told DJ it’s looking into the matter but found no evidence of a hacking attempt, while Astrazeneca declined to comment.

 - Bloomberg