As Turkey faces obstacles in the Syrian military operation it plans for Manbij and northeast Syria, drama is developing in Idlib province, where 12 Turkish posts overlook what is supposed to be a de-escalation zone.

Since the beginning of January, Hayat Tahrir al-Sham — a coalition of Islamist factions in northern Syria — has routed the opposition groups Turkey had merged under the banner of the National Liberation Front.

The clashes erupted Jan. 1 after the National Liberation Front's Nour al-din al-Zenki Movement killed five Hayat Tahrir al-Sham fighters in Darat Izza, drawing in other National Liberation Front groups such as Ahrar al-Sham, Thuwar al-Sham and Biyareq al-Islam. For the National Liberation Front factions, the outcome was a debacle. In 10 days, they lost nearly 90 localities to Hayat Tahrir al-Sham, greatly complicating the September deal Turkey and Russia had reached in Sochi to establish the de-escalation zone around Idlib in areas including parts of western Aleppo, northwestern Hama and northeastern Latakia.

Here is a brief overview of how the current situation developed.