The US military said it destroyed a drone fired by the Yemeni Houthis on Saturday, with another presumed to have crashed into the Red Sea.
There were no reports of damage or injuries from ships in the vicinity, the US Central Command (CENTCOM) said in a statement.
CETNCOM also said it destroyed five unmanned surface vessels and one UAV in self-defence, in Houthi-controlled areas of Yemen.
"It was determined these weapons presented an imminent threat to merchant vessels and US Navy ships in the region," the statement read.
Months of Houthi attacks in the Red Sea have disrupted global shipping, forcing firms to re-route to longer and more expensive journeys around Southern Africa, and stoked fears that the Israel-Hamas war could spread to destabilise the wider Middle East.
The US and Britain have carried out strikes against Houthi targets in response to the attacks on shipping.
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