A helicopter carrying Iranian President Ebrahim Raisi and Foreign Minister Hossein Amir Abdollahian crashed on Sunday, according to reports from Iran's state media and the country's mission to the United Nations. However, search and rescue teams have yet to locate the crash site after nearly five hours due to heavy fog hampering the operation.

State news agency IRNA reported that a massive search involving 16 teams is underway to try to find the downed helicopter. "Given the complexities of the region, connection has been difficult, and we are hoping that the rescue teams reach the helicopter and can give us more information," Interior Minister Ahmad Vahidi told state television, as reported by IRNA.

President Raisi was on an official visit to the mountainous Eastern Azerbaijan province in northwestern Iran when the incident occurred. His delegation was traveling in a convoy of three helicopters, with the other two aircraft reaching their destinations safely, state media said.

In addition to Raisi and Abdollahian, the governor of Eastern Azerbaijan province was also on board the missing helicopter, which crashed in an area called Varzaghan, according to state media reports cited by Reuters.

No information has been provided yet on any potential casualties or the condition of the president and others. The cause of the crash also remains unknown at this point.

Under Iran's law, if the president dies, power transfers to the first vice president until an election can be held within six months. The current first vice president is Mohammad Mokhber, a conservative politician, according to Reuters.

State media has not confirmed the locations or status of Raisi, Abdollahian and the other passengers as the search operation continues amid difficult terrain and weather conditions. More details are expected once the crash site can be accessed by rescue workers.

The reports from Iranian state media outlets like IRNA were corroborated by Iran's mission to the United Nations, according to the Associated Press. However, the AP noted that Iran's state media has yet to report on any casualties from the crash or confirm the whereabouts and condition of the president as of late Sunday night.