Two Syrian opposition monitoring groups say rebel fighters have seized the Syrian side of a major Syria-Iraq border crossing from the Islamic State group.

Fighters from the New Syria Army militia took the Tanaf border crossing Friday night, the Syrian Observatory for Human Rights says.

The Local Coordination Committees network reported Saturday that one IS fighter was killed in the fighting and several more were injured.

The IS group had controlled the crossing, located in the Homs province in southeast Syria, since government forces withdrew in May 2015.

The Observatory says the rebel fighters had crossed into Syria from Jordan, suggesting they are backed by the United States.