Syrians stand and look out on the street of the ancient Syrian city of Palmyra on May 18, 2015, a day after Islamic State (IS) group jihadists fired rockets into the city, killing several people. Fierce clashes have rocked Palmyra's outskirts since IS launched an offensive on May 13 to capture the 2,000-year-old world heritage site nicknamed 'the pearl of the desert'.  AFP PHOTO /STR        (Photo credit should read STR/AFP/Getty Images)