Turkey launched a military operation against Kurdish fighters in northeast Syria on Wednesday just days after U.S. troops pulled back from the area, with warplanes and artillery striking militia positions in several towns in the border region.

Turkish President Recep Tayyip Erdogan, announcing the start of the action, said the aim was to eliminate what he called a "terror corridor" on Turkey's southern border, but European countries immediately called on Ankara to halt the operation.

Thousands of people fled the Syrian town of Ras al Ain toward Hasaka province, held by the Kurdish-led Syrian Democratic Forces. The Turkish airstrikes had killed two civilians and wounded two others, the SDF said.