The Ukrainian airliner that crashed killing 176 people was likely downed in error by an Iranian missile, Canadian Prime Minister Justin Trudeau said Thursday.

Trudeau confirmed intelligence from various sources led to that conclusion, but only a “full and credible investigation” could definitely confirm it.

“The evidence indicates the plane was shot down by an Iranian surface-to-air missile,” Trudeau said at a news conference. “We recognize that this may have been done (by) accident.

“I want answers,” Trudeau said.

The Boeing 737-800 was just airborne from an Iranian airport when it crashed. Most passengers were Iranian or Iranian

Read more: Trudeau: Ukranian plane likely downed by Iran missile