Ukraine leader warns against 'speculation' after plane crash

Ukrainian President Volodymyr Zelensky on Wednesday warned against speculation about the crash of a Ukrainian passenger plane near Tehran which killed more than 170 people.

"I ask everyone to keep from speculating and putting forth unconfirmed theories about the crash," he wrote on Facebook, as he cut short a holiday in Oman and flew back to Ukraine.

The Ukrainian Embassy in Tehran said the plane went down "due to an engine problem".

It said that "an act of terror is ruled out" for the moment, adding that the Ukrainian ambassador was at the crash site.

Zelensky ordered the creation of a crisis team to handle the accident including top ministers and managed by the country's national security agency.

The agency said it has information about 168 passengers who had checked in for the flight as well as nine crew members, putting the total estimated number of people on the plane at 177.

"We have prepared emergency planes to send to Tehran... to fly out the bodies of the victims, we are waiting a confirmation by Iran for their departure," Zelensky wrote.

The crew members were all Ukrainian nationals, according to the embassy in Iran.

Officials said the most of the passengers on board were non-Ukrainians.

The flight from Tehran to Kiev operated by Ukraine International Airlines took off from the Iranian capital's airport and crashed in Tehran province in the early hours of Wednesday.