United States officials believe the Ukrainian International Airlines Boeing 737-800 aircraft was hit by a missile.

The Ukrainian government had earlier said it was examining whether a missile strike brought down the aircraft  but Iran ruled this out.

The crash came   hours after Iran launched a ballistic missile attack against Iraqi military bases housing U.S. troops in a confrontation with Washington over the U.S. drone strike that killed the Iranian Revolutionary Guard general Qassem Soleimani.

The President of the United States, Donald Trump said on Thursday that he had “suspicions” about what happened to the plane.

“Somebody could have made a mistake on the other side. Some people say it was mechanical. I personally don’t think that’s even a question,” Trump said.

Amid tensions heightened by the US killing of General Soleimani on  January 3, Iran has said it will not hand over the recovered black box flight recorders to Boeing, the plane’s manufacturer or to the United States.