"The strike was requested by the partnered forces, who had identified the target location as an ISIS [Daesh] fighting position," the US Central Command said in a press release.
"The target location was actually a forward Syrian Democratic Forces fighting position."
Tabqa, which is believed to be the last stronghold of Daesh is located some 40 kilometers (25 miles) away from Raqqa. Taking the city is part of the operation to liberate Raqqa with the offensive against Tabqa having started on March 21.
In November 2016, the SDF, which predominately consists of Kurdish fighters but also includes members of the Syrian Arab Coalition, launched an operation called the Rage of Euphrates to seize control over Syrian Raqqa, the de facto Daesh capital.
Earlier in April, the Kurdish People’s Protection Units (YPG) have gained control of all the roads leading to the northern Syrian city of Tabqa.