Iran has shot down a US military drone using a surface-to-air missile, Iranian and American military officials said, amid an escalating row over alleged attacks on oil tankers in the Strait of Hormuz.
The two sides differed in their accounts of both the model of the drone and where it was at the time. The US military said it was in international airspace, while Iran's Revolutionary Guard said it had entered Iranian territory near Kouhmobarak district in Hormozgan province.
Two Iranian state media outlets carried statements referring to the "spy" drone as an RQ-4 Global Hawk and said it was destroyed on Thursday morning.
The US military, which initially declined to confirm reports of a downed drone, later said a US Navy MQ-4C Triton drone was hit by an Iranian missile over international waters.
Tensions have remained high between the two countries since US president Donald Trump withdrew from the international nuclear deal with Iran, which granted it sanctions relief in exchange for tight controls on the state's nuclear programme.
But the Strait of Hormuz, a key shipping lane in the Gulf of Oman close to where Iran says the drone was shot down, has been a more immediate flashpoint in recent weeks amid a spate of attacks on oil tankers.
The US and its ally Saudi Arabia have blamed Iran for the incidents, and the US has deployed an aircraft carrier to the Middle East and additional troops to add to the tens of thousands already in the region.
Iran has denied involvement but said that security for the Strait of Hormuz was its responsibility, demanding American forces be withdrawn.
Additional reporting by agencies