Syrian rebels launched a surprise offensive into President Bashar Assad’s northwestern Alawite heartland on Sunday, capturing a military airport north of Aleppo and half a dozen villages east of the port city of Latakia while pushing toward the leader’s hometown of Qardaha on Monday.

Ten mainly Islamist brigades, including two groups that are affiliated with the terrorist organization Al Qaeda, advanced south from Qardaha to the outskirts of the village of Aramo, taking advantage of the rugged terrain there, activists told the news agency Reuters.

Videos taken by activists showed rebels firing Russian Konkurs anti-tank missiles from a rocky terrain and praying next to a tank after taking the army position overlooking Salma, a Sunni village on the edge of the an-Nusayriyah Mountains which shield the Alawite homeland on the coast from the Sunni provinces in the east.

The area is the main recruiting ground for Assad’s core praetorian guard units who have proved to be the most effectively in combatting the rebellion along with fighters from the Lebanese militant organization Hezbollah — which is also financed by Syria’s ally Iran.

The offensive risk both exacerbating the sectarian divide in Syria three years into its civil war and undermining Assad’s suspected strategy of shielding the Alawite province as well as major cities in the west of the country, including the capital Damascus, from an insurgency that has effectively taken control of swaths of the Euphrates River valley in the east.

Reports of ethnic cleansing earlier surfaced from towns in the an-Nusayriyah Mountains, raising suspicion that the regime was carving out a homogenous enclave for Assad’s Alawite sect, while some of the heaviest fighting this year took place in and around the city of Qusayr, strategically situated on the highway from Damascus to Homs, a hotbed of rebel activity, as well as Tartus on the Mediterranean coast, a government stronghold.

Whether Assad’s aim is to retreat into the Alawite homeland altogether, centered on the cities of Tartus in the south and Latakia in the north with an oil terminal at Baniyas in between, or secure a larger belt of territory that includes Damascus and Homs, he could not afford to lose Qusayr and give the rebels a permanent opening into such a redoubt. Loyalist forces recaptured the city in early June after weeks of heavy fighting.