Several Turkish armored vehicles and tanks have entered rebel-controlled northwestern Syria in the latest reinforcements sent in by Ankara amid a Syrian government offensive that this week brought the two countries’ troops into a rare direct confrontation. The offensive by the Syrian government, backed by its ally Russia, has been unfolding to secure a strategic highway that runs along rebel-controlled territory, advancing on rebel-held areas and towns and displacing hundreds of thousands of people. The latest Turkish deployment on Friday came a day after Syrian troops captured a key town along the highway. The offensive has displaced over half a million people.