Iranian officials have denied claims that they mistakenly shot down a Ukrainian passenger jet. The plane crashed early Wednesday morning soon after takeoff from Tehran’s airport, killing everyone on board.

CBS News has learned that U.S. officials are confident 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.

Read the rest of the story at CBS News.