Iran's air defence force has shot down an "unknown" drone in the country's south-west, the official IRNA news agency reported on Friday.
The agency said that Iranian forces hit the drone in the early morning at Mahshahr, a port in the oil-rich Khuzestan province and on the Arabian Gulf.
The report did not say whether the drone was a military or commercially available device, said the Associated Press.
Provincial governor Gholamreza Shariati told IRNA that the drone belonged to a "foreign" country and that parts of the drone had been recovered in a nearby lagoon.
He said the drone had violated Iran's airspace.
Joseph Dempsey, Research Associate for Defence and Military Analysis at the International Institute for Strategic Studies, geo-located footage of the supposed drone and said it did appear consistent with report of a Surface-to-Air Missile launch from Mahshahr.
But after slowing and analysing the clip he said: "However, I suspect Iran state media footage actually shows SAM failing after launch - cutting off before possible ground impact."
US Central Command said on Friday that reports that a US drone had been shot down over Iran were "incorrect".
Centcom said on Twitter that all American equipment had been accounted for.
In June, Iran shot down a US surveillance drone in the Strait of Hormuz. Tehran said the drone "violated" its territorial airspace, while the US called the missile fire "an unprovoked attack" in international airspace over the narrow mouth of the Arabian Gulf.
Regional tensions remain high over Tehran's collapsing nuclear deal with world powers, which the US unilaterally withdrew from over a year ago.
Reuters reported that Iran's semi-official Tasnim news agency said the drone "downed over Iran's airspace with the army's domestically made Mersad surface-to-air missile".
Iran's Arabic-Language al-Alam TV channel said that residents had heard the sound of a missile being fired on Friday morning.
As well as international concern over the nuclear deal and security for ships in the Gulf, tensions are high after the attacks in September on two Saudi Aramco oil facilities, which Saudi Arabia and the US have said they believe were perpetrated by Iran.