Earlier this week, a report from Radio Farda said Iran wants Ukraine to sign a memorandum of understanding in which the families of the crash victims would sign away their future rights for legal compensation.

Iran has arrested several people and promised to hold them to account, but Ukraine nonetheless launched its own criminal investigation.

The strike, and Iran's retaliation, raised fears of wider war and frustrated some lawmakers who said Trump had given them shifting justifications for the attack.

TSB investigators are seeking access to the plane's flight data recorders, known as the "black boxes," to help with the work being led by Iran's civil aviation authority.

The leader of Hezbollah, which is closely aligned with Iran, said the strikes were the "first step down a long path'' that will ensure U.S. troops withdraw from the region.

Videos of the protest show what looks to be hundreds of Iranians in front of Amir Kabir University raising their fists, chanting and clapping their hands. A candlelit vigil was held earlier at the university for the victims of the shooting.

'I would speculate that he had a role in supplying Canada’s enemies. And those enemies subsequently hurt Canadians.' a former official with Canadian Security Intelligence says.

Soleimani's death prompted an Iranian retaliatory missile strike on Tuesday night against two U.S. bases in Iraq.

The Democratic war powers resolution seems certain to pass over solid Republican opposition.

Both sides appeared to step back on Wednesday after Iran launched a series of ballistic missiles at two military bases housing American troops in Iraq without causing any casualties.