A top commander in Syria has warned that a resurgent ISIS is starting to take advantage of the chaotic fall of Bashar al Assad.
The lightning advance by opposition groups on Damascus has been the focus of much attention but the revolution has created power vacuums across the country.
What's happening in Syria is an opportunity but also a moment of great jeopardy.
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As the country struggles to emerge from the darkness and brutality of the Assad regime many groups are vying for position in this new reality - and it is in that space that Islamic State in Iraq and Syria (ISIS) is trying to gather strength.
In the northeast, the Kurds are worried about what may happen.
One of the most important figures in this region is General Abdi Mazloum, the commander-in-chief of the Syrian Democratic Forces (SDF).
He is warning the West that ISIS is already trying to exploit the turmoil.
"ISIS is now stronger in the Syrian desert. Previously, they were in remote areas and hiding, but now they have greater freedom of movement since they face no issues with other groups and are not engaged in conflict with them," he tells Sky News.
He adds: "In the areas under our control, their activities have also increased. Just a few days ago, three members of the Internal Security Forces were killed near al Hassakah in an ISIS operation."
Since the civil war began, Syria has been divided into different areas of control.
Regional and international powers also held sway in certain parts - the Turks, the Russians, the Iranians and the United States.
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The SDF was created in 2015 as a coalition aimed at fighting ISIS.
The SDF is primarily composed of Kurdish fighters from the YPG (People's Protection Units) and YPJ (the female equivalent of the YPG) and is backed and trained by the United States.
Ideologically, it is aligned with the territory known as Rojava, which is an autonomously administered region.
Following the defeat of ISIS in 2019, it also ended up controlling large areas of northeast Syria - which is now a flashpoint.
Opposition rebel groups want to move into those cities, towns and villages and already there have been clashes.
General Mazloum hopes the situation can be managed.
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He says local commanders are communicating with their counterparts in rebel groups to keep a lid on the tensions.
But the relationship with Turkish-backed forces - like the Syrian National Army - is much more difficult to manage.
The fighting with these groups has been more intense.
Turkey is alarmed by the Kurdish influence on its border and is trying to roll it back.
It has launched incursions into Syria and has sponsored militias to achieve its goals.
Ankara views the YPG and YPJ - a core part of the SDF - as not much different from the PKK, a separatist movement that it has designated a terrorist organisation.
If the tensions are not kept under control they could escalate significantly.
At the moment the Americans are attempting to act as an intermediary.
But General Mazloum says the clashes with Turkish-backed groups are making it more difficult to concentrate on stopping ISIS from regenerating.
As a result of the security situation, they have had to suspend counterterror operations.
"At the moment, joint operations against ISIS are halted. This is not a decision but rather a military reality, as the coalition is also preoccupied with the ongoing conflict. Therefore, I stress that if these attacks persist, joint operations will remain suspended," he says.
He also warns that it's possible that ISIS prisoners kept in detention camps and prisons could escape in the chaos.
ISIS encourages attacks on these jails as a way of freeing its most ideologically hardened recruits.
"Generally, the effectiveness of our forces and those of the coalition against ISIS diminishes when we are focused on protecting civilians and our communities, as efforts are redirected toward the ongoing conflict. This is why I say that if the fighting continues and intensifies, it will play into ISIS's hands," the general adds.
"Frankly, there is currently a significant threat to the security of these detention centres."
While Syrians celebrate the end of the Assad regime, there is great peril ahead and the spectre of the re-emergence of Daesh, the other name that ISIS is known as - a group the West thought had been defeated.
(c) Sky News 2024: Kurdish US-allies halting anti-ISIS operations in Syria because of thr