"US Central Command can confirm that a US Navy Broad Area Maritime Surveillance (or BAMS-D) ISR aircraft was shot down by an Iranian surface-to-air missile system while operating in international airspace over the Strait of Hormuz at approximately 11:35 p.m. GMT on June 19, 2019", the statement said.
Reports that the drone was inside Iranian airspace when it was shot down are "false," Urban said, calling the incident "an unprovoked attack."
Earlier in the day, the Iranian Revolutionary Guard Corps reported that Tehran shot down a US surveillance RQ-4 Global Hawk drone over Hormuzgan province in Iran's south. Later, the IRGC commander-in-chief said that the move meant to send a "clear message" to Washington.
The United States confirmed the news saying that the drone was downed with a surface-to-air-missile over the Strait of Hormuz. However, Washington insisted that it had not violated Iran's airspace.
This follows last week's incidents in which two oil tankers were reportedly attacked in the Gulf of Oman. Washington rushed to blame Tehran for the alleged attack, but the Islamic Republic denied any involvement.
Days after the incidents, the Pentagon greenlighted the dispatching of an additional 1,000 troops to the region.
Relations between Washington and Tehran have exacerbated following the US withdrawal from the JCPOA and subsequent adoption of "maximum pressure" policy against Iran.
Iran last month stopped curbing its stocks of enriched uranium and heavy water and vowed to continue suspending its commitments under the 2015 accord if the remaining signatories fail to shield it from tough US sanctions.