Iran has confirmed that its forces have shot down a drone and said it belonged to a foreign country, state news agency IRNA reported.
Provincial governor Gholamreza Shariati told IRNA that the drone belonged to a "foreign" country and that parts of it had been recovered in a nearby lagoon.
The report did not say whether the drone was a military or commercially available device.
The army downed the unmanned aircraft over Khuzestan province before dawn using a Mersad surface-to-air missile, said the Tasnim news agency, which is close to Iran's ultra-conservatives.
Iran's Arabic-Language al-Alam TV channel said: "Residents of Imam Khomeini port city heard the sound of a missile being fired on Friday morning".
A US military official told Fox News on Friday that all American drones are accounted for and none have been shot down.
Shariati added that the drone was downed by the Army Air Defense unit in the Southwest and its debris were found in the marshlands in the suburb of Mahshahr.
The incidents come amid soaring tensions between Tehran and Washington since President Donald Trump unilaterally abandoned a landmark 2015 nuclear deal a year ago and reimposed crippling sanctions.
Israel says it has carried out hundreds of air strikes in neighboring Syria, some of them against Iranian targets, to prevent Tehran from establishing a presence there.
Yemen's Iran-backed Huthi rebels claimed responsibility, but the U.S. says the attacks involved cruise missiles from Iran and amounted to "an act of war".