Islamic State is planning a mass prison break to free thousands of its fighters detained in Syria, according to Iraqi officials.

The terror group is feared to be trying to exploit the power vacuum left by the fall of the Assad regime to regroup just as Israeli bombs destroy the last of Syria’s military assets.

Abdul Karim Abd Fadhil, the head of Iraq’s national security service, said on Sunday that IS was planning to target the prisons where thousands of its fighters have been held for years.

His warning about prison security followed concerns voiced by US senator Lyndsey Graham. He said an IS jailbreak would be a “nightmare” for both America and Europe.

At least 40,000 people associated with IS remain in detention camps run by the Syrian Democratic Forces (SDF), a US-backed Kurdish fighting force that controls most of north-east Syria.

About 9,000 well-trained, battle-hardened IS fighters are spread across multiple prisons, the largest being al-Hasakah and al-Shaddadi. Hundreds were killed in a previous prison break attempt at al-Hasakah in 2022.