The helicopter crash that killed Iran含羞草研究社檚 president and foreign minister has sent shock waves around the region.

Iranian state media on Monday said that President Ebrahim Raisi, the country含羞草研究社檚 foreign minister, Hossein Amirabdollahian, and others had been found dead after an hourslong search through a foggy, mountainous region of the country含羞草研究社檚 northwest. State TV gave no immediate cause for the crash.

Here含羞草研究社檚 what we know so far.

WHO WAS ON BOARD AND WHERE WERE THEY GOING?

The helicopter on Sunday was carrying Raisi, Amirabdollahian, the governor of Iran含羞草研究社檚 East Azerbaijan province and other officials, according to the state-run IRNA news agency.

Raisi was returning after traveling to Iran含羞草研究社檚 border with Azerbaijan to inaugurate a dam with Azerbaijan含羞草研究社檚 President Ilham Aliyev when the crash occurred in the Dizmar forest in East Azerbaijan province.

IRNA said the crash killed eight people including three crew members aboard the Bell helicopter, which Iran purchased in the early 2000s.

HOW DID THE SEARCH OPERATION GO?

Iranian officials said the mountainous, forested terrain and heavy fog impeded search-and-rescue operations, which continued overnight.

The president of the Iranian Red Crescent Society, Pir-Hossein Koulivand, said Sunday evening that 40 search teams were on the ground despite 含羞草研究社渃hallenging weather conditions.含羞草研究社� Because of the bad weather, it was 含羞草研究社渋mpossible to conduct aerial searches含羞草研究社� via drones, Koulivand said, according to IRNA.

It was not until early Monday that officials announced the helicopter had been found and all of its occupants were dead.

HOW WAS THE CRASH SITE FOUND?

Early Monday, Turkish authorities released what they described as drone footage showing what appeared to be a fire in the wilderness that they 含羞草研究社渟uspected to be wreckage of a helicopter.含羞草研究社� The coordinates listed in the footage put the fire about 20 kilometers (12 miles) south of the Azerbaijan-Iranian border on the side of a steep mountain.

Footage released by IRNA showed what the agency described as the crash site, across a steep valley in a mountain range. Soldiers speaking in the local Azeri language said: 含羞草研究社淭here it is, we found it.含羞草研究社� Shortly after that, state TV in an on-screen scrolling text said: 含羞草研究社淭here is no sign of life from people on board.含羞草研究社�

HOW WILL RAISI含羞草研究社橲 DEATH IMPACT IRAN?

Raisi was seen as a protege to Iran含羞草研究社檚 supreme leader Ayatollah Ali Khamenei and a potential successor for his position within the country含羞草研究社檚 Shiite theocracy.

Under the Iranian constitution, if a president dies, the country含羞草研究社檚 first vice president 含羞草研究社� in this case, Mohammad Mokhber 含羞草研究社� would become president. Khamenei has publicly assured Iranians that there would be 含羞草研究社渘o disruption to the operations of the country含羞草研究社� as a result of the crash.

WHAT HAS INTERNATIONAL REACTION BEEN?

After news broke of the search operation, countries including Russia, Iraq and Qatar made statements of concern about Raisi含羞草研究社檚 fate and offered to assist in the search.

Azerbaijani President Aliyev offered any support necessary. Relations between the two countries have been chilly due to Azerbaijan含羞草研究社檚 diplomatic relations with Israel, Iran含羞草研究社檚 regional arch-enemy.

Saudi Arabia, traditionally a rival of Iran although the two countries recently made a rapprochement, said it stands by 含羞草研究社淚ran in these difficult circumstances.含羞草研究社�

There was no immediate official reaction from Israel. Last month, following an Israeli strike on an Iranian consular building in Damascus that killed two Iranian generals, Tehran launched hundreds of missiles and drones at Israel. They were mostly shot down and tensions have apparently subsided.

The U.S., which has its own history of tensions with Tehran, also has yet to comment publicly on Raisi含羞草研究社檚 death.

READ ALSO:

Abby Sewell, The Associated Press