Iran fired missile at US drone before attack on tankers

CNN:

In the hours before the attack on the two tankers in the Gulf of Oman on Thursday, the Iranians spotted a US drone flying overhead and launched a surface-to-air missile at the unmanned aircraft, a US official told CNN.

The missile missed the drone and fell into the water, the official said.
Prior to taking fire, the American MQ-9 drone observed Iranian vessels closing in on the tankers, the official added, though the source did not say whether the unmanned aircraft saw the boats conducting an actual attack.

Still, it is the first claim that the US has information of Iranian movements prior to the attack.
CNN has not seen any imagery from the US drones.

Iran has strenuously denied any involvement in the attack.

The same official also said in the days prior to the attack, a US reaper drone was shot down in the Red Sea by what is believed to be an Iranian missile fired by Houthi rebels.
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 The US should be preparing strikes on Iranian anti-aircraft sites.  I suspect the drone that was fired upon has video of the Iranians attacks on the tankers.  Both Pompeo and Trump make clear that Iran was responsible.