Iranian President Ebrahim Raisi and seven others, including Foreign Minister Hossein Amirabdollahian, died in a helicopter crash in May caused by challenging climatic conditions, including dense fog, according to an Iranian military report.

The crash occurred in a mountainous area of northwestern Iran, with no signs of sabotage found.

Raisi, considered a protégé of Supreme Leader Ayatollah Ali Khamenei, was seen as a potential future leader of Iran, CBS News has reported.

He was the second Iranian president to die in office, following Mohammad Ali Rajai’s death in 1981.

Written by B.C. Begley