The bells of St. Peters rang out as Pope Benedict XVI left The Vatican by helicopter:
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A US Twitter study has found that there are almost 50,000 active pro-Islamic State accounts, but say the number could be as high as 90,000.
In its first test, the 30-kilowatt military laser burned through a truck's engine in a matter of seconds.
Islamic State militants have begun to raze ancient ruins at the site of the Assyrian city of Nimrud.