Sources were quoted in the Wall Street Journal said the UK-based people were of Moroccan descent. The Independent was unable to verify this claim, although it known that the Paris attacks ringleader, Abdelhamid Abaaoud, was born in Morocco.

One of the 11 terrorists behind the attacks that left 130 dead and more than 350 people wounded in the French capital, also travelled to Birmingham and London earlier this year, according to a separate report in The Guardian, which The Independent was also unable to verify.

Before he died during a siege by French security forces in the St Denis area of Paris on November 18, Abaaoud boasted in Isis propaganda that he had been able to travel unnoticed into and through Europe.

Assistant Chief Constable Marcus Beale of the West Midlands Police called the reports “speculative” but admitted that the force’s counter terrorism unit was “working hand in hand with counter terrorism colleagues in London, the national counter terrorism network and security services to provide support to the French and Belgian investigators.”

He added they were also addressing “any associated terrorism threat to the UK.”

“We work tirelessly to counter terrorism,” he said. “Our absolute priority is to ensure the safety and security of people who live, work and visit the West Midlands area.”

Meanwhile, two "armed and dangerous" men accused of helping Paris attacks suspect Salah Abdeslam have been identified by Belgian prosecutors.

They said Abdeslam traveled to the Hungarian capital twice in September in a rental car, and was accompanied on one occasion by men using fake identity cards under the names Samir Bouzid and Soufiane Kayal.

One of the fake identities was used to rent a house in Auvelais which has been searched by police.

The other, under the name Bouzid, was used four days after the Paris attacks to transfer €750 (£540) to the niece of Abdelhamid Abaaoud, who died following a police assault in Saint-Denis on November 18, they said.

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