DAMASCUS — A week after taking back the historic town of Palmyra, Syrian troops and their allies on Sunday captured another town controlled by the Islamic State in central Syria, state media reported.

The push into the town of Qaryatain took place under the cover of Russian airstrikes and dealt another setback to the extremists in Syria. An activist group that monitors the Syrian civil war said that government forces were in control of most of the town after Islamic State fighters withdrew to its eastern outskirts.

The advance came a week after Syrian forces recaptured Palmyra, and it is strategically significant for the government side. The capture of Qaryatain deprives the Islamic State of a main base in central Syria and could be used by government forces to launch attacks on militant-held areas near Iraq.

Qaryatain, which used to be home to a sizable Christian population, is midway between Palmyra and the capital, Damascus.

Activists said last summer that Qaryatain had a mixed population of around 40,000 Sunni Muslims and Christians, as well as thousands of internally displaced people who had fled from the nearby city of Homs. Many of the Christians fled the town after it came under attack by the Islamic State.

Dozens of Qaryatain’s Christians and other residents have been abducted by the extremists. While the town was under Islamic State control, some were released, others were made to sign pledges to pay a tax imposed on non-Muslims.

Extremists blew up and destroyed some of the world’s most precious relics at Palmyra’s archeological sites during their 10-month reign there; the ancient Saint Eliane Monastery near Qaryatain was bulldozed and destroyed shortly after Islamic State took the town in August.

Christians made up about 10 percent of Syria’s prewar population of 23 million people.

The Syrian army command said in a statement that troops have ‘‘restored security and stability to Qaryatain and farms surrounding it.’’ The statement, read by an army general on state TV, said the oil and gas pipelines in the area will be secured and supply routes for the militants between the eastern desert and the Qalamoun region will be cut.

A Syrian army general, speaking live from Qaryatain with the Lebanon-based Al-Mayadeen TV, said troops were dismantling bombs placed by extremists and will prepare to launch more attacks on Islamic State areas.

‘‘Fighting was going from one house to another,’’ another army officer told Al-Mayadeen TV also speaking from inside Qaryatain. He added that Islamic State suicide attackers were trying to block the push by the army into the town.

The Britain-based Syrian Observatory for Human Rights said intense fighting was underway in Qaryatain as government troops fought to capture all parts of the town. The Observatory reported that Islamic State fighters had withdrawn from much of the town toward the eastern suburbs of Qaryatain.

The militants have suffered major defeats in Syria in recent months amid intense airstrikes by Russian warplanes.

Earlier Sunday, the Observatory reported that fighting in northern Syria the previous day killed 12 fighters belonging to the Lebanese militant Hezbollah group, which has been fighting alongside President Bashar Assad’s troops in Syria’s civil war.

Militants led by Al Qaeda’s Syria branch — the Nusra Front — attacked the Hezbollah unit in the northern village of al-Ais.

Although Nusra Front is not part of a US-Russia-engineered truce between the Syrian government forces and Western-backed rebels, the fighting has threatened to undermine the cease-fire, which has largely held for over a month.

In Iraq on Sunday, government forces said they had taken the northern edge of the Islamic State-held town of Hit, 85 miles west of Baghdad, after hundreds of roadside bombs littering the surrounding area slowed progress for days.

The US-led coalition said Iraqi forces were working to surround the town.

Hit lies along a supply line linking the extremist group’s fighters in Iraq to those in neighboring Syria. Iraqi and coalition officials say retaking the town will be a key step before an eventual push on Mosul.

The operation to recapture Hit was launched last week by counterterrorism forces, but their progress has been slowed by hundreds of roadside bombs as well as efforts to safeguard thousands of trapped civilians.

The Islamic State produces roadside bombs on an industrial scale. Its fighters use these bombs defensively, placing the devices to essentially create minefields to impede advancing government forces.