European authorities have taken action to take down a cyberespionage campaign believed to be linked to Iran's powerful Revolutionary Guard, the first operation of its kind since Tehran signed a nuclear treaty, according to security researchers.

The hacker group — dubbed "Rocket Kitten" by security experts who have been hunting the hacker group since early 2014 — has mounted cyberattacks on high-profile political and military figures globally since that time, according to researchers from several cybersecurity firms who have monitored its activities.

The action could hamper Tehran's efforts to gather sensitive intelligence from rivals including Saudi Arabia, Israel, Turkey, the United States as well as ally Venezuela, which were among the nations targeted.