Turkey pledges more support for war on ISIS as tanks roll into Syria

Turkish tanks have crossed into Syria as part of a joint operation with U.S.-backed coalition forces to free a border town held by Islamic State (ISIS), according to the state-run Turkish news agency. The effort began this morning with Turkish artillery and warplanes bombarding the town of Jarablus just across the Syrian border. Turkey promised Tuesday to take a more active role in fighting ISIS alongside the United States and its allies. But the move puts Turkey on a collision course with the Syrian Kurds, a U.S.-backed rebel group in the region that opposes the Syrian government and ISIS. The Kurds and Turkey have a long history of animosity. In Turkey today, U.S. Vice President Joe Biden told the Kurds to retreat out of the fighting area or risk losing U.S. support.