A U.S. fighter plane on Sunday shot down a Syrian warplane in response to an attack on U.S.-backed rebel forces fighting the Islamic State.
It was the first time an American plane shot down a Syrian aircraft and raised concerns that the conflict could escalate and draw foreign powers further into an already complex war.
The plane was shot down after pro-Syrian forces attacked elements of the Syrian Democratic Forces, a U.S.-backed alliance of local militias opposed to the Islamic State, the U.S. military said in a statement.
The Syrian forces wounded a number of SDF troops and drove the U.S.-backed troops out of a small town south of Tabqah, a strategic area west of Raqqa, the defacto capital of the Islamic State. The Syrian Democratic Forces are engaged in a major offensive to drive the militants from Raqqa.
Coalition aircraft conducted a “show of force,” which usually means aircraft flying low and fast or strafing near enemy forces, in an effort to scare off the pro-Assad troops.
The U.S.-led coalition also contacted their Russian counterparts in an effort to warn the pro-Assad forces to refrain from attacking the Syrian Democratic Forces.
The Syrians appeared to ignore the request and a Syrian SU-22 dropped bombs on the SDF fighters. The Syrian plane was immediately shot down by a U.S. F/A-18E Super Hornet.
The U.S. military has said it does not want to engage in a conflict with the Assad regime and is focused on defeating the Islamic State. But the U.S. military said it would defend U.S.-backed forces when necessary.
“The coalition does not seek to fight Syrian regime, Russian, or pro-regime forces partnered with them, but will not hesitate to defend coalition or partner forces from any threat,” the U.S. military said in a statement.
Iran and Russia are supporting the Assad regime and has deployed forces in Syria.
The U.S. military has several hundred advisers operating with Syrian Democratic Forces, which it is also supplying the organization with weapons and equipment.
As territory controlled by the Islamic State has shrunk the risks of conflicts between an array of forces operating in the country, including Russia and Iran, have increased. The forces are converging in a shrinking area as the Islamic State is pushed out of its strongholds.
In recent weeks U.S. aircraft have launched several strikes on pro-Assad militias operating in southern Syria.
Contributing: Greg Toppo, USA TODAY. Follow Jim Michaels on Twitter: @jimmichaels