Iranian officials have denied claims that they mistakenly shot down a Ukrainian passenger jet and accused the United States of “spreading lies” about intelligence suggesting they did.

The plane crashed early Wednesday morning soon after takeoff from Tehran’s airport, killing everyone on board.

U.S. officials are said to be confident that Iran shot down the jetliner in the hours after the Iranian missile attack on U.S. targets earlier this week.

There were 176 people killed in the crash: 82 Iranians, 63 Canadians, 11 Ukrainians, 10 Swedish, four Afghan, three German and three British nationals.

Canada’s Prime Minister Justin Trudeau has also said that his country has intelligence from its own agencies pointing to Iranian missiles hitting the jet.

United States Reaction:

Secretary of State Mike Pompeo responded Friday morning to Iran’s flat denial of intelligence suggesting it mistakenly shot down a civilian passenger jet by accepting that it was “possible it’s a mechanical failure.”

But Pompeo told Fox News, “we’ll have to see if, in fact, it’s the case that there was something more insidious than this.”

Officials have said U.S. and Canadian intelligence shows a pair of Iranian surface-to-air missiles were fired from the Tehran area early Wednesday morning — just hours after Iran launched about 15 ballistic missiles at Iraqi bases housing U.S. troops — which likely brought down the Ukrainian International Airlines jet, killing everyone on board.