A mansion belonging to the Qatari royal family sits on the outskirts of Palmyra, an ancient Syrian city famed for its Roman ruins. (Agence France-Presse via Getty Images)

Syrian government forces recaptured the historic city of Palmyra from the Islamic State on Thursday, aided by Lebanon’s Hezbollah, the Russian military and, indirectly, U.S. airstrikes.

The government victory came nearly three months after the Islamic State marched back into the town in a surprise assault that appeared to have taken the Syrian army unawares.

The Syrian army announced in a statement read on state television Thursday evening that its forces were in complete control of Palmyra after a push on the town in recent days that saw Islamic State defenses rapidly collapse.

The Islamic State surge into Palmyra in December was the first offensive conducted by the militants in more than 18 months and raised fears that they were on the advance again. The relatively swift recapture by government loyalist forces suggested the surge was a temporary aberration, the result more of weakness on the part of a thinly spread Syrian army that has come to rely on foreign allies for its survival.

[Our journey to the front lines in the fight against ISIS]

(Reuters)

The militants are on the retreat in multiple locations along their long, jagged front line with a variety of forces in Iraq and Syria, including in the Iraqi city of Mosul and on the outskirts of their self-proclaimed capital, Raqqa.

The offensive to retake Palmyra was supported by the Lebanese Shiite militia Hezbollah, whose fighters have been instrumental in securing President Bashar al-Assad’s survival over the past five years. A video that aired on the Hezbollah television station Al-Manar showed Hezbollah fighters camping out in the desolate mountains surrounding Palmyra and advancing on the town through the sandy, stony wilderness.

The Syrian offensive was also aided by Russian airstrikes, according to Russian news reports quoting Russian Defense Minister Sergei Shoigu. The Syrian army statement thanked Syria’s “friends” for their help in the offensive, singling out Russia. Russian military intervention in 2015 sealed the survival of Assad by adding the muscle of Russian airstrikes to the manpower contributed by Iranian-backed militias on the ground.

The Syrian statement did not mention the role of the United States, which has also stepped up strikes in the Palmyra area in recent weeks. During the last 10 days of February, the U.S. military conducted 23 strikes against Islamic State fighting units, tanks, storage facilities and command centers, according to the daily tally issued by the U.S. Central Command. Altogether in February, U.S. warplanes carried out 45 strikes in Palmyra.

[Russian drone shows extent of the damage to Palmyra’s Roman amphitheater]

The U.S. military has denied coordinating strikes directly either with Russia or the Syrian government but has said in the past that it is striking Palmyra to prevent military equipment captured by the Islamic State from being used by the militants in battles elsewhere against U.S.-backed forces.

This was the fourth time Palmyra has changed hands in less than two years, and each time its renowned ruins have been further damaged. Since capturing the city for a second time, the militants have claimed further attacks against its monuments.

It is still too early to tell how extensive the latest damage is. Photographs posted by a Russian news agency and widely shared on social media showed a Syrian soldier standing in the ruins of the Roman amphitheater, where a Russian orchestra played at a victory concert last year. Although part of the facade has crumbled and the theater is strewn with rubble, the amphitheater appears still to be largely intact.

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