Erdogan vows to 'crush the heads' of Kurds if they don't withdraw; both sides trade blame for violating cease-fire

Turkish President Recep Tayyip Erdogan on Saturday promised to "crush the heads" of the Kurds in Syria if they don't fall back from the border's safe zone, according to reports.

The threat comes as both Turkey and the Kurdish-led Syrian Democratic Forces (SDF) claim the other is violating terms of a 120-hour cease-fire brokered by Turkey and the U.S. on Thursday.

Violence continued in northeast Syria despite the five-day peace agreement, a source told Fox News.

Dave Eubank with Free Burma Rangers, a private military company that provides emergency medical assistance, was on the ground near the Syrian border town of Ras al-Ayn trying to help trapped and wounded Kurds.