A new report shows at least 30,000 people from more than 100 countries have joined ISIS in Syria and Iraq since 2011, with more than 250 of them being American. Turkey has been accused of turning a blind eye to the thousands of foreign fighters crossing its border into Syria. Turkish officials told CBS News they're now cracking down, but that it's impossible to stop the flow of Islamic extremists to groups like ISIS. Holly Williams reports from Gaziantep, Turkey, along the Syrian border.
