In this picture taken Friday, April 1, 2016, soldiers look over damage at the historical Bel Temple in the ancient city of Palmyra in the central city of Homs, Syria. Explosions rocked the ancient town of Palmyra on Friday and on the horizon, black smoke wafted behind its majestic Roman ruins, as Syrian army experts carefully detonated hundreds of mines they say were planted by Islamic State militants before they fled the town. AP
DAMASCUS, Syria 鈥� Syrian troops have found a mass grave containing the bodies of 42 people executed by ISIS jihadists in Palmyra, as Washington warned the group鈥檚 leader will eventually 鈥渢aste justice鈥�.
ISIS has in recent months claimed responsibility for deadly attacks in Brussels and Paris, but has lost ground in Syria and Iraq.
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Days after Syrian troops backed by Russian forces recaptured Palmyra and its ancient ruins, the army 鈥渦ncovered a mass grave of officers, soldiers, members of the popular committees (pro-regime militia) and their relatives,鈥� a military source told AFP on Saturday.
Twenty-four of the victims were civilians, including three children, he said, asking not to be named.
鈥淭hey were executed either by beheading or by shooting.鈥�
In a major symbolic and strategic coup for President Bashar al-Assad, the Syrian army last Sunday recaptured Palmyra and its UNESCO World Heritage Site, which ISIS had overrun in May 2015.
During their nearly 10-month occupation of Palmyra, the jihadists executed at least 280 people, according to the Syrian Observatory for Human Rights, a Britain-based monitor which confirmed the discovery of the mass grave.
Soon after ISIS stormed Palmyra, it shot dead 25 soldiers in the ancient Roman theatre.
It later released a video of the mass killing in which the executioners appeared to be children or teenagers.
Syria鈥檚 five-year war has left at least 270,000 people dead. Few mass graves have been found, however.
Nearly a week on, few of Palmyra鈥檚 up to 70,000 residents have returned.
Next stop: Sukhna
鈥淧eople fear reprisal by the regime, and also the mines planted all over the city by ISIS,鈥� Observatory director Rami Abdel Rahman told AFP.
鈥淚n addition, many houses were flattened by Russian air strikes before Palmyra was reclaimed,鈥� he added.
About 70 kilometers (45 miles) to the west, Syrian troops on Saturday pounded the ISIS-held city of Sukhna, which the army wants to take back in order to consolidate its grip over Palmyra.
鈥淚f the regime takes Sukhna, it will use it as a launching pad for an operation against Deir Ezzor province,鈥� in eastern Syria, along the Iraqi border, which is mostly controlled by ISIS, Abdel Rahman said.
The Syrian army has previously said the takeover of Palmyra would allow it to extend operations against ISIS in the east and around Raqa, the jihadists鈥� de facto capital in the north.
At least 40 mostly foreign ISIS members, including 18 child soldiers, were killed in raids Thursday on a village in Deir Ezzor province, the Observatory said.
It was one of the single highest tolls that ISIS has suffered in a single strike since it emerged in Syria in 2013, the monitor said.