Syrian government and allied forces have taken the last major town in Homs province from Islamic State, the Syrian Observatory for Human Rights said on Saturday, as the army advances toward militant strongholds in the east of the country.
The town of al-Sukhna lies some 50 km (30 miles) northeast of the ancient city of Palmyra, which was captured by government forces in March.
al-Sukhna is some 50 km from the administrative frontier of Deir al-Zor province, which is almost entirely under Islamic State control.
A Hezbollah media unit said government and allied forces were making considerable progress inside the city of Sukhna. Lebanon's Hezbollah group fights on the side of Syrian President Bashar al-Assad in the Syrian conflict.
Syrian state news agency SANA reported earlier on Saturday that the army was advancing into al-Sukhna from three directions.
Islamic State is losing ground fast in Syria to separate campaigns waged by the Russian-backed Syrian government on the one hand, and to U.S.-backed Kurdish forces and their allies on the other.
Government forces, backed by the Russian air force and Iran-backed militias, have also been advancing against IS in Hama province and in southern areas of Raqqa province.
U.S.-led operations against IS are currently focused on taking Raqqa city in northern Syria.