At least 30 militants with the Islamic State (IS) group were killed during ongoing battles with the Syrian army forces in the surrounding of the ancient city of Palmyra, a monitor group reported Saturday.

The battles in the vicinity of this millennia-old oasis city have been gaining momentum in recent days, as the Syrian forces were said to be waging a counter-offensive to recapture Palmyra from the IS hands.

A total of 12 government forces were also killed during recent battles in Palmyra, according to the Syrian Observatory for Human Rights, which tracks the Syrian war.

On Thursday, the pan-Arab al-Mayadeen TV said the Syrian forces had launched an offensive to expel the IS group from the ancient city of Palmyra in the eastern countryside of Homs province.

The army forces have been only few kilometers from the western entrance of Palmyra, after the troops managed to retake around 15 kilometers west of the city amid the withdrawal of many IS militants toward the eastern and central parts of the city.

The military operation will continue until the recapture of Palmyra, the TV said, adding that the government forces are attacking from three directions.

Palmyra contains the monumental ruins of a great city that was one of the most important cultural centers of the ancient world.

After storming Palmyra, the IS militants blew up the city's military prison and several Islamic tombs.

From the 1st to the 2nd century, the art and architecture of Palmyra, standing at the crossroads of several civilizations, married Graeco-Roman techniques with local traditions and Persian influences, according to the UNESCO.

Syria has many prehistoric, Greek, Byzantine and Islamic heritages. Before the crisis, Syria had attracted many multinational archaeological missions coming for searching new clues of historical facts on the development of civilizations.

The UNESCO has listed six Syrian sites on the World Heritage List, including the old cities of Damascus and Aleppo, al-Madhiq castle, the Krak des Chevaliers, the ancient city of Bosra and Palmyra and the ancient villages in northern Syria.