What's the most logical way to complete this passage?

Along the Turkish border hundreds of thousands of Syrian refugees listen to the distant pop of shells and rattle of machine-gun fire as ISIS renewed its attacks on their home city of Kobani today. Between 140,000 and 180,000 ethnic Kurds have so far left the city for the safety of Turkey, fearing another massacre if Islamic State militants overrun the peshmerga fighters protecting them. While the evacuation has been largely peaceful so far, today clashes erupted between armed Turkish police and Kurdish refugees as they tried to march back to the border and stage a protest, no longer able to bear  the sound of the fighting.

They tried to invade
Kobani last night but they were repelled.