The Security Service of Ukraine (SBU) is “reviewing" a missile hit and a terrorist attack as possible explanations behind the plane crash but urges everyone not to “jump into hasty conclusions,” Ivan Bakanov, the head of the service, said in statement on Friday.

“Indeed, the version that a missile of a Tor anti-aircraft missile system hit [the plane] is attracting the greatest public attention today. However, it’s enough to open the manual for a surface-to-air missile system to raise a number of questions that need further answers,” Bakanov said.

Bakanov said his agency is “carefully analyzing the information,” pointing towards the plane crash having been the result of a potential terrorist attack. He urged the public not to jump into “hasty conclusions.”

Some context: Bakanov's comments come a day after leaders of the UK and Canada said they have intelligence saying the Ukrainian plane was shot down by a surface-to-air missile.

A video that appears to show a missile being fired into the Tehran sky and striking an object, around the same time that a Ukrainian plane crashed just after taking off from the city's airport, surfaced Thursday.