(ABC NEWS) -- A U.S. Navy fighter jet shot down a Syrian regime fighter jet on Sunday that had dropped bombs on Syrian rebel forces fighting ISIS in Syria.
The U.S.-led coalition said in a statement that it's focus is on fighting ISIS, and not fighting the Syrian regime or Russian forces, but it will not hesitate to defend coalition or partner forces coming under attack.
The incident occurred in the town of Ja'Din, south of Tabqa, Syria, which had recently been retaken from ISIS by the Syrian Democratic Forces (SDF), an umbrella group of Syrian Kurdish and Arab rebel forces supported by the U.S. in the fight against the militant group.
SDF came under attack from regime forces in favor of Syrian President Bashar al-Assadaround 4:30 p.m. Syria time. A number of SDF fighters were wounded in the assault, and the SDF soon left Ja'Din.
Coalition aircraft conducted a show of force overhead that stopped the initial pro-regime advance towards the town.
"Following the Pro-Syrian forces attack, the coalition contacted its Russian counterparts by telephone via an established 'de-confliction line' to de-escalate the situation and stop the firing," said a statement from Operation Inherent Resolve, the U.S.-led coalition fighting ISIS.
"At 6:43 p.m., a Syrian regime SU-22 dropped bombs near SDF fighters south of Tabqah and, in accordance with rules of engagement and in collective self-defense of coalition partnered forces, was immediately shot down by a U.S. F/A-18E Super Hornet," said the statement.
Ja'Din is approximately two kilometers north of an established East-West SDF-Syrian Regime de-confliction area.
In the statement, the coalition stressed its goals and that it will defend its partnered forces.
"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," it said.
"The demonstrated hostile intent and actions of pro-regime forces toward coalition and partner forces in Syria conducting legitimate counter-ISIS operations will not be tolerated," it added.
The shootdown is the latest escalation between the U.S.-led coalition and pro-regime Assad forces in Syria.
Over the last four weeks, the U.S. has conducted three airstrikes at pro-regime Assad forces, backed by Iran, that have moved into a deconfliction zone around the town of at Tanf in southwest Syria, which is the location of a coalition training base for local forces fighting ISIS.