A helicopter carrying Iranian President Ebrahim Raisi has crashed, multiple news sources, as officials said extensive search operations were under way but were being impeded by poor weather conditions.

Iranian state media said the crash occurred on Sunday near Jolfa in Iran’s East Azerbaijan province, in the north of the country.

The exact details of what happened are still unclear, and it is not yet known whether Raisi was on board the helicopter.

The helicopter – one of three travelling in a convoy – made a “hard landing” after it got into difficulties in heavy fog in the north of the country, state media says.

Iranian state media have used the phrase “hard landing” to describe the reported crash of the Iranian President’s helicopter.

Hard landing is a phrase often used by authorities in Russia to describe incidents when aircraft crash. It is commonly used by the Russian Defence Ministry when reporting incidents with military aircraft.

There is no update yet on the condition of those on board.

The details of what happened remain unclear, but here’s a look at what we know so far:

  • According to local media, Raisi was heading to the city of Tabriz, in the north west of Iran, after returning from the border with Azerbaijan, where he opened the Qiz Qalasi and Khodaafarin dams
  • The helicopter was one of three travelling in a convoy
  • Iran’s interior minister says rescuers are still trying to reach the site, but their efforts are being hampered by poor weather conditions
  • A reporter with Fars news agency says visibility in the mountainous and wooded area was down to only about five meters. The area is about 50km to the north of Tabriz
  • Ahmad Alirezabeigi, an Iranian MP for the city of Tabriz, says that emergency rescue workers have yet to find the location of the helicopter carrying the president
  • He says two other two helicopters in the convoy landed safely