There are fears ISIS could be making a comeback, with the sleeper terror cell launching a number of random, deadly attacks.
ISIS beheadings and suicide bombings are returning to levels last seen when the jihadis ruled vast swathes of territory.
Ten thousand of the bloodthirsty fanatics are reportedly gathering in northern Iraq and Syria to unleash the kind of violence witnessed when they rampaged through the countries in 2014, The Sun reported.
Recent days have seen ISIS violence escalate in the desert province of Deir Ezzor – also known as Deir al-Zour – and the city of the same name, in northeastern Syria.
ISIS was last year reported to have established control of territory in the desert around 24kms from the centre of the town of Deir Ezzor – the first land it has held since the end of the Caliphate.
A Syrian researcher named Ali, who works for the non-governmental organisation The Syrian Observatory for Human Rights, told the BBC that ISIS terror was taking many forms.
“Beheadings, bombings, motorcycle suicide, assassination and kidnappings – and we’re just talking about a small area east of Deir al-Zour city,” he said.
In a recent attack, 40 people were killed when an ISIS sleeper cell ambushed a bus and civilians rarely come out after dark when the jihadis emerge.
He said at night people “are in fear” and “in the hands” of ISIS fighters as the population begins to evacuate.
“They used to go to the authorities but nobody responds. They always say we don’t have enough arms to fight them, so they evacuate,” he said.
ISIS once controlled a vast swath of territory across Iraq and Syria, seized in terrifying offensive in 2014, culminating in its leader Abu Bakr al-Baghdadi declaring an Islamic Caliphate in a Mosul mosque.
The bloodthirsty jihadis ruled with extreme brutality before a coalition of Kurdish forces backed by western airpower pushed them into their final pocket of territory in Baghouz, Syria in 2018.
But since their apparent defeat, they have been slowly rebuilding, despite the death of Baghdadi at the hands of US special forces.
Sirwan Barzani, a commander of the Kurdish Peshmerga forces stationed near the northern city of Erbil said the terrorists had taken advantage of a lull in operations against them.
His forces estimate there are some 7000 ISIS fighters ready to strike – though the United Nations puts the figure even higher, at 10,000.
ISIS activities have been on the rise across the globe, from Africa to the Philippines.
At the end of last year, the jihadis beheaded more than 50 people and chopped up the bodies of victims in a brutal attack in northern Mozambique, according to reports.
Their attacks in the east African country are getting nearer to the country’s oil reserves.
The jihadis launching a daring attack last December just 13 miles from an installation run by French company Total in Cabo Delgado province.
Last year, ISIS claimed responsibility for the sickening bombings in Sri Lanka which killed 321 people on Easter Sunday.