Backed by intense US airstrikes, the Kurdish YPG have advanced into the important Syrian border town of Tel Abyad, seizing much of the town amid heavy fighting, and threatening to cut off the most important ISIS supply route from their capital of Raqqa to Turkey.

YPG officials touted the attack as a sweeping victory, and claimed ISIS morale appeared to be much worse than in previous engagements in the area. Some YPG officials were also talking advancing, with US blessing, on Raqqa itself.

Turkish officials expressed surprise at how quickly the YPG took much of Tel Abyad, and also disquiet about that fact, complaining that the Kurds are carving out a large region along their border and ethnically cleansing Arabs, sending refugees pouring into Turkey again.

Turkey had initially endorsed the rebellion against Syria with an eye on a new Arab nationalist government tamping down Kurdish autonomy, but as the war has dragged on, the Kurds have ended up with effective independence, and Turkey has been stuck with ISIS and al-Qaeda across much of their border.