COURTESY: RT's RUPTLY video agency, NO RE-UPLOAD, NO REUSE - FOR LICENSING, PLEASE, CONTACT br Over 4,000 Islamic State terrorists, reinforced by tanks, have started an offensive to retake the key Syrian city of Palmyra after regrouping themselves, the Russian Center for Reconciliation in Syria says.br br READ MORE: br br RT LIVE br Subscribe to RT! br Like us on Facebook Follow us on Twitter Follow us on Instagram Follow us on Google+ Listen to us on Soundcloud: br RT (Russia Today) is a global news network broadcasting from Moscow and Washington studios. RT is the first news channel to break the 1 billion YouTube views benchmark.