Iranian President Ebrahim Raisi and Foreign Minister Hossein Amirabdollahian were killed in a helicopter crash in mountainous terrain near the Azerbaijan border on Sunday, Reuters reported citing officials and state media.

A provincial governor and other officials who were also on board during the crash that occurred at 1 PM local time, are presumed dead.

While an official cause of the accident has not been determined, it was initially reported that the chopper had a rough landing due to bad weather and heavy fog in the area.

Rescue teams had searched through dense forest for more than 12 hours, at times calling off the search due to the fierce weather.

Raisi, who is believed to be the potential successor to Supreme Leader Ayatollah Ali Khamenei, had traveled to the country’s border with Azerbaijan, where he jointly inaugurated a new dam with Azerbaijani President Ilham Aliyev.

“President Raisi, the foreign minister and all the passengers in the helicopter were killed in the crash,” a senior Iranian official who allegedly refused to be named told Reuters.

State TV reported that images from the site showed the aircraft slammed into a mountain peak, although there was no official word on the cause of the crash, Reuters reported.

Raisi 63, was elected president in 2021, and since taking office has ordered a tightening of morality laws, overseen a bloody crackdown on anti-government protests and pushed hard in nuclear talks with world powers.