Beirut (AFP) - The Islamic State jihadist group has blown up parts of the Temple of Bel in Syria's ancient city of Palmyra, a monitor and activists said.The Syrian Observatory for Human Rights said late Sunday that the jihadist group had placed explosives inside the famed temple, at least partially destroying the building considered Palmyra's most significant.Mohamed Hassan al-Homsi, an activist from Palmyra, also reported the partial destruction on Sunday night, a week after IS destroyed the Baal Shamin temple at the historic Greco-Roman site."They laid the explosives today, using booby-trapped boxes and barrels that were already prepared by IS," he said. "This was the most important temple for tourists and for the people of Palmyra.