Lawyers for the environmental watchdog were informed on Tuesday by authorities that Russia’s Investigative Committee had ended the year-long probe into the case involving the so-called Arctic 30.

Activists from the group’s flagship Arctic Sunrise attempted to scale the Prirazlomnaya platform in September last year in an attempt to stop production, which subsequently began.

The 30, including 28 protesters and two freelance journalists, were arrested, jailed and charged, initially on charges of piracy, before this was changed to hooliganism.