Tension between Iran and the United States has spiked since last year

Iran's elite Revolutionary Guards have shot down a U.S. "spy" drone in the southern province of Hormozgan, the Guards' news website, Sepah News, said on Thursday.

Tension between Iran and the United States has spiked since last year, when President Donald Trump exited a 2015 nuclear deal between Tehran and major powers and reimposed sanctions on the country.

State news agency IRNA carried the same report, identifying the drone as an "RQ-4 Global Hawk'.

"It was shot down when it entered Iran's airspace near the Kouhmobarak district in the south," the Guards' website added.

Washington accuses Iran of being involved in explosive strikes on two oil tankers in the Gulf of Oman last week and four tankers off the United Arab Emirates on May 12, both near the Strait of Hormuz, a major conduit for global oil supplies.

Iran has denied the accusation.

The RQ-4 Global Hawk unmanned aircraft system (UAS) can fly at high altitudes for more than 30 hours, gathering near-real-time, high-resolution imagery of large areas of land in all types of weather, maker Northrop Grumman says on its website.