The US Central Command (CENTCOM) said in a statement that five other troopers also sustained injuries in the Sunday incident, without identifying the soldiers or providing more details regarding the circumstance of the deadly event.
The slain troops were part of the so-called US-led coalition, which was formed in 2014, with a purported aim of fighting the Takfiri Daesh terrorist group in Iraq but it was later expanded to include territories in eastern and northern Syria.
However, the so-called coalition has repeatedly been accused of targeting and killing civilians. It has also been largely incapable of fulfilling its declared aim of eliminating Daesh.
The Pentagon has admitted to killing almost 500 civilians in the US campaign over the past three years, but monitoring group Airwars says the actual number is about 3,800.
Back in March 17, a US-led airstrike in the then Daesh-held city of Mosul killed 105 civilians sheltered in the bottom floors of a structure.