As many as four of the 26 long-range cruise missiles that Russia said it fired at Syrian targets landed instead in Iran, two U.S. defense officials said Thursday.
The officials said it's unclear whether the errant missiles, launched from Russian ships in the Caspian Sea, caused any significant damage in Iran. One of the officials said the number of missiles that went off course was four. The officials were not authorized to discuss the matter publicly and spoke on condition of anonymity.
The Russian government said Wednesday it launched 26 cruise missiles, hitting targets in the Syrian provinces in the north and northwest. It made no mention of any missiles going astray. The missiles' intended flight paths took them over Iran and Iraq.
The cruise missile attack was part of an expanding Russian military campaign in Syria that has deepened the divide between Moscow and Washington over how to approach the Syrian civil war and the presence there of Islamic State fighters.
The missiles also have added a new layer of uncertainty to efforts by the Pentagon to ensure the safety of U.S. and coalition pilots who are flying daily in Syria airspace. Russia also is flying attack and reconnaissance missions over Syria.
Russia says its intervention is aimed at helping the Syrian government defeat the Islamic State group, but local activists and U.S. officials say the strikes have also targeted Western-backed rebels and have had the effect of propping up the government of President Bashar Assad.