It is reported that Syrian military aircraft have been bombarding a town just metres away from the Turkish border.
Ras al-Ain had been captured just a few days earlier by rebel forces, sending thousands of Syrians to the already overflowing refugee camps.
The latest assault saw many more headed for the camps as well as to hospitals.
In the 24 hours after the town had been taken by the rebels around 9,000 people fled across the frontier.
It has been one of the largest influxes during the 19-month conflict.
With winter temperatures beginning to bite, there are now reportedly around 120,000 Syrians sheltering in the Turkish camps.
Ankara, which is increasingly concerned about fighting close to the border, has been talking with its NATO allies over the deployment of surface-to-air missiles to defend against a spillover of violence.