BEIRUT: Syrian government forces and their allies from Lebanon's Hezbollah reached the outskirts of Palmyra in their push to drive ISIS militants from the ancient town, activists said Tuesday.

The advancing forces reached the town's southwestern gateway, located about 5 kilometers (3 miles) from its famed Roman ruins, according to the activist-run Palmyra Coordination Committee.

The activist group also reported airstrikes across the town Tuesday morning. The Britain-based Syrian Observatory for Human Rights and Hezbollah's media outlets also reported the advances.

It was the second such campaign for the city in the past year.

The government lost control of Palmyra in December, less than one year after reclaiming it from ISIS with Russian support. Archeologists have decried what they say is extensive damage to the city's famed ancient ruins.

Palmyra was Syria's top tourist attraction before war gripped the country in 2011, drawing tens of thousands of visitors each year. Syrians affectionately refer to the town as "the bride of the desert."

Drone footage released by Russia's Defense Ministry earlier this month showed new damage to the facade of Palmyra's Roman-era theater and the adjoining Tetrapylon - a set of four monuments with four columns each at the center of the colonnaded road leading to the theater.

A 2014 report by a U.N. research agency disclosed satellite evidence of looting while the ruins were under Syrian military control. Opposition factions have also admitted to looting the antiquities for funds.