HAMILTON, Canada

The US has lost roughly a dozen MQ-9 Reaper drones during its ongoing air campaign against Iran, with the unmanned aircraft downed by Iranian missile strikes or "mistakenly" destroyed by a Gulf ally, according to a report published Monday.

A Wall Street Journal (WSJ) report, citing US military officials, said the losses have not slowed Washington down, adding that the US is flying more than 10 Reaper drones over Iran at any given time, targeting Tehran's missile systems and other military capabilities.

The drones entered the campaign two weeks ago when US President Donald Trump ordered strikes on Iranian military sites. Since then, they have hit hundreds of targets across the country, the report noted.

The Reaper can stay airborne for up to 20 hours, allowing it to track and strike mobile missile launchers.

When a drone is badly damaged, operators deliberately destroy it to keep its sensitive technology out of Iranian hands, officials told WSJ.

Regional escalation has raged since the US and Israel launched a joint offensive on Iran on Feb. 28, killing so far more than 1,200 people, including then-Supreme Leader Ali Khamenei.

Tehran has retaliated with drone and missile strikes targeting Israel, along with Jordan, Iraq, and Gulf countries, which it says are targeting "US military assets."