MOREK, Syria (AP) — A heavily fortified Turkish observation post in the northwestern village of Morek stood surrounded on all sides by Syrian troops Saturday, a testament to the rapid advance of President Bashar Assad’s forces in Syria’s northwest over the past three weeks as rebel defenses collapsed.

Syrian authorities took a group of journalists to tour the observation post, several newly captured villages and the town of Khan Sheikhoun, which was a major rebel stronghold until it was taken by government forces earlier this week.

In Morek, there was no sign of friction between the Turks and the Syrian troops who took positions hundreds of meters away from the observation post. The journalists were kept about 1.2 mile away from the Turkish post.

Relations between Turkey and Syria have deteriorated sharply since Syria’s crisis began in 2011, with Damascus accusing Ankara of undermining its security by allowing thousands of foreign fighters to come battle the Syrian army.

Turkey is a strong backer of opposition gunmen fighting Assad’s forces and has 12 observation posts in northwestern Syria as part of an agreement reached last year with Russia, a main backer of the Syrian government.