Islamic State have established a stronghold in mainland Europe, a Sunday Mirror investigation reveals.
Terrorists are secretly buying land in an isolated village, surrounded by deep woodland.
Security services think the area in Bosnia is used for ISIS training camps and could be a base for devastating terror attacks on the West.
Crucially, the location gives IS a key strategic position due to its proximity to the Mediterranean which is used by extremists from Syria, Iraq and North Africa.
At least 12 ISIS fighters trained in the village of Osve have left for Syria in recent months and five are reported to be dead.
Terror expert Dzevad Galijasevic said: “From this village a large number of people went to Syria and are going constantly.
“The chosen location of some of the properties is on a hill, where there is no possibility to approach without being seen. It is clear that the source of the terrorist threat is right there. It is a major threat.
“There is no one there who isn’t ready to respond to the summons to jihad.”
We visited the hilltop village 60 miles from Sarajevo and six miles from the town of Maglaj afternoon.
It is not mapped by GPS and is only accessible by steep and winding roads barely wide enough for cars to pass.
A number of houses there appear to have been abandoned or only half built and it is not overlooked by any other settlement.
A number of villagers wore Islamic-style clothing, including two women wearing burkas.
Our guide – our driver and translator – said we were being watched and it was too dangerous to photograph them.
Clearly worried, the dad-of-one said: “We should leave now – our presence here is beginning to cause suspicion. This is a beautiful place but is incredibly dangerous.
“You cannot underestimate the possible threat here. If they see the camera all hell will break loose.”
It is understood that notorious ISIS supporter Harun Mehicevic is among fanatics who bought land in the area. He has purchased two hectares.
Mehicevic fled Bosnia during the 1990s Balkan wars and settled in Melbourne, Australia, where he is considered one of the country’s most dangerous men.
In one ranting sermon, he reportedly told an audience of potential recruits: “Allah will help the mujahideen (holy warriors) establish an Islamic State where Muslims can live with dignity and honour.”
Other known terrorists believed to have bought land in the village include Jasin Rizvic and Osman Kekic, who are both now fighting with ISIS in Syria.
Muslim leader Izet Hadzic – arrested by Bosnia’ and Herzegovina’s security service Sipa in a raid – is also understood to have property in the village, as have many others who have gone to fight in Syria and Iraq.
One villager told our investigators that locals fear the area is a “nest for terrorists”.
The man, who does not want to be named, said: “We regularly hear gunshots coming from the woods up there for long periods at a time. It happens every week.
“I don’t know what they are doing, whether it is target practice or something like that, but it happens regularly.
“It is really concerning to hear such notorious members of ISIS are buying land. They keep themselves to themselves but it is better not to ask questions.
“It worries me that I am bringing up my children here. Now could be time to move out but it is not so easy to sell.”
Bosnia is an ideal position for jihadis travelling illegally from Syria to Greece, via Turkey, and then through Macedonia and Serbia.
Guns and other weapons are easier to obtain in Bosnia than in other parts of Europe due to illegal ownership following the conflicts of the 1990s.
Five months ago, anti-terror cops raided the village of Gornja Maoca in the north of the country following reports of houses flying the ISIS flag.
The area is home to followers of the strict Sunni Islam Wahhabi movement. It has been raided by police several times over the past decade due to suspected links with radical groups.
A report on jihadism in Bosnia said: “Returning foreign fighters from Syria and Iraq – battle-hardened, skilled in handling arms and explosives, and ideologically radicalised – pose a direct threat not only to the security of Bosnia and Herzegovina, but also of the region and beyond.”
The report, The Lure of the Syrian War: The Foreign Fighters’ Bosnian Contingent, said that between 2013 and 2014, 156 Bosnian men and 36 women travelled to Syria, taking 25 children with them.
It said 48 men and three women had officially returned by last January.
The authors, Sarajevo University associate political science professor Vlado Azinovic and Islamic theologian Muhamed Jusic, also found that Bosnia was ill-prepared to deal with the threat.
The report said: “There is a lack of co-ordination between local law-enforcement agencies on (foreign fighter) issues.”
Kristina Jozic of security service Sipa said: “The return of individuals participating in the conflict in Syria, fighting with ISIS, is undoubtedly a security challenge and a threat, the extent of which is hard to determine.”
She said: “Sipa continuously performs checks of all allegations that can be linked to terrorist activities in any way, whether that is financing, recruiting or other activities related to terrorism.”
She added that the village is under surveillance following a police raid in May.
Director of the Centre for Security Studies in the Bosnian capital Sarajevo, Armin Krzalic, said: “Bosnians who went to fight for Islamic State will be treated as a threat to security upon their return whether they have land here or not.”