Turkish-backed forces are fighting street by street inside the Syrian border town of Ras al Ain. They’re firing at Kurdish groups in a military offensive launched last week, after the U.S. began withdrawing its troops from the region, effectively clearing the way for Turkey. Turkey is ramping up its assault, ignoring new U.S. sanctions and global outcry. The country’s military strengthened its presence along the border with convoys on Tuesday. Meanwhile, the Syrian army and its ally Russia are taking advantage of the U.S. retreat. Convoys with Syrian and Russian flags entered the flashpoint city of Manbij on Tuesday. Some residents welcomed the advance – and the return of government control – by unfurling the Syrian flag. Russian officials said the Syrian army now controlled more than 385 square miles around the city. The U.S., whose troops were seen driving near Qamishli in Syria’s far northeast on Tuesday, continues to call for an immediate halt to Turkey’s operations. Trump has attempted to punish Ankara – just a week after agreeing to the U.S. pullout and effectively reversing 5 years of support for the Kurds But the sanctions – mainly steel tariff hikes and paused trade talks – were panned by critics as too weak. The offensive has forced an estimated 160,000 people to flee, and raised fears about the security of prison camps holding some 12,000 Islamic State members in the region.