Kurdish forces charged with maintaining security in the Syrian province of Deir Ezzor have apprehended two of the most dangerous "Islamic State of Iraq and Syria" (ISIS) elements, a Syrian Democratic Forces (SDF) official said.

The move comes as part of a surveillance operation to track down and break apart ISIS sleeper cells, which have been proven to be behind a number of bombings that have caused civilian casualties, SDF officer Farhad Khoja said.

"ISIS sleeper cells are the primary target of the SDF and the Kurdish People’s Protection Units (YPG), particularly in Deir Ezzor," he told Diyaruna.

There have been reports that some ISIS elements have managed to escape arrest by hiding among civilians or in hideouts, where they have been planning attacks against security personnel and civilians, he said.

On the eastern outskirts of Deir Ezzor city, Khoja said, a unit of the SDF anti-terror forces (YAT) arrested Anwar Abdel Rahman Haddouchi, a Belgian national known to be one of the group’s most dangerous elements.

Haddouchi is suspected of being involved in dozens of crimes against civilians, he said, and of involvement in the attacks in Paris in 2015 and Belgium in 2016.

He is said to have beheaded more than 100 people in the marketplace of the former ISIS stronghold of al-Raqa, AFP reported.

The YPG, in co-ordination with the SDF, also was able to ascertain the presence of a number of other ISIS elements in rural Deir Ezzor, Khoja told Diyaruna.

During a raid, these forces detained Mohammed Ramadan Eid al-Atallah, who had been in charge of financing ISIS sleeper cells in the region, he said.

Weapons, ammunition, cash and documents related to activities on behalf of ISIS were found in al-Atallah's possession, Khoja said.

Anti-ISIS operations continue

Operations to eliminate ISIS remnants are continuing, Khoja said, in order to prevent the group's re-emergence and prevent future attacks.

The success of these operations "cripples their capabilities, or causes them to make mistakes that lead to the discovery of their hideouts and their arrest," he said.

Operation Inherent Resolve and the SDF have detained more than 225 suspected ISIS fighters in the last four months, the international coalition said in a Saturday (August 31st) statement.

Additionally, the statement said, these forces have removed 4,000 pounds of explosives from the battlefield during the last two months.

Regional security in north-east Syria is essential for stability and reconstruction efforts that further contribute to the enduring defeat of ISIS, it said.

"Our partners continue to conduct difficult operations to relentlessly pursue ISIS and eliminate a future for them in north-east Syria," said US Air Force Maj. Gen. Eric Hill, Special Operations Joint Task Force-Operation Inherent Resolve (SOJTF-OIR) commander.

The SOJTF-OIR is the special operations arm of the international coalition.

"The SDF’s continued efforts are critical to the safety and stability of the region," he said.