Moscow claims return of more than 40,000 people to Syria's Ghouta

However, the Syrian Observatory for Human Rights monitoring group on Tuesday said the reports were false.

The return of tens of thousands to Eastern Ghouta would indicate a modicum of security coming to the area after the regime retook more than 90 percent of the rebel-held enclave. The campaign to seize the area began February 18, after the regime – with Russian backing – began a deadly air and ground offensive.

More than 1,600 of Eastern Ghouta's 400,000 have died since the offensive began in February. 

The government offensive in Ghouta has been one of the deadliest of the war, killing more than 1,600 civilians, according to the Observatory. At least 170,000 people, including civilians and rebel fighters, have also been evacuated out of the area.

In the past 24 hours, an additional 1,100 Jaish al-Islam fighters and their families have left the town of Douma in Eastern Ghouta, Russia's defence ministry also said.

Jaish al-Islam is the last remaining rebel group in Eastern Ghouta but has repeatedly denied agreeing to leave the area. On Wednesday, the regime gave the group a final, three-day ultimatum to leave the enclave. 

Elsewhere in Syria, Russian and Syrian military officers told rebels in Eastern Qalamoun, about 25 miles northeast of Damascus, they must accept regime rule or leave.

The regime's recent advances have been some of the most decisive military gains since forces took Eastern Aleppo in 2016. The UN and rights groups have criticised the regime and its Russian ally for the heavy bombardment of civilians areas and for not implementing a February 30-day ceasefire in Eastern Ghouta. 

The Syrian conflict began when the Baath regime, in power since 1963 and led by President Bashar al-Assad, responded with military force to peaceful protests demanding democratic reforms during the Arab Spring wave of uprisings, triggering an armed rebellion fuelled by mass defections from the Syrian army.

According to independent monitors, hundreds of thousands of civilians have been killed in the war, mostly by the regime and its powerful allies, and millions have been displaced both inside and outside of Syria. The brutal tactics pursued mainly by the regime, which have included the use of chemical weapons, sieges, mass executions and torture against civilians have led to war crimes investigations.

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