A Syrian man suspected of being an Islamic State terrorist, is believed to be in hiding among refugees in Calais' Jungle migrant camp. The man, who is being hunted by armed police, is described as a 'category S' criminal who poses a threat to national security.

The suspect is believed to have left Syria in late August and travelled overland to northern France. It is feared he is planning to cross the Channel, either by ferry or on the Eurostar, to commit acts of terror in the UK.

Details of the 'Lone Wolf' extremist, who is said to be sleeping rough in Calais, were published in France's La Voix du Nord newspaper this morning. La Voix du Nord's report read: "An Islamic State combatant believed to be in Calais is being actively hunted by the authorities. He left Syria at the end of August and hopes to reach Britain where he intends to commit terrorist acts ... He is the subject of most wanted person notice and is considered a threat to state security."

The French police dossier on the alleged terrorist includes a photograph of the suspect and a physical description. The newspaper claims that French police have been ordered to locate the man and apprehend him, but have been instructed to proceed with caution in view of the threat he poses.

The report contradicts earlier reassurances by Calais police that the camps around the port town are the focus of intensive intelligence gathering operations involving up to 40 detectives and that there are no suspected terrorists hiding among the thousands of refugees living in the camps.

Speaking last May, spokesman Steve Barbet said: "There is full and complete vigilance in Calais, nationally and elsewhere with regard to threat by jihadists or other criminal networks with potential involvement in people smuggling."

According to The Times, police have refused to confirm the latest reports of a search for a lone terrorist, however refugee charities working in the region said they were aware that the manhunt was underway.

The news comes amid claims ISIS are using Europe's refugee crisis to smuggle thousands of terrorists into Europe. An ISIS operative claims 4,000 gunmen have already been smuggled into Europe.

There are currently 3,500 migrants of Asian and African origin sleeping rough at an approved camp on the outskirts of Calais and 120 women and children in sheltered accommodation. Another 1500 migrants are living on wasteland close to the motorways leading to the ferry port where they attempt to break into the Eurostar station or sneak into UK-bound cars and lorries, and even risk their lives walking along the tracks to southern England.