EUROPE’S open borders are putting Britain’s security at risk of a deadly terror attack, a former police chief has warned.
The terrifying warning comes after it was revealed the terrorist behind the Berlin Christmas market attack travelled through three counties undetected before being killed in Italy.
Anis Amri travelled from Berlin to the French Alps, and then onto Milan in Italy - covering 1,000 miles without being stopped at any point despite being the most wanted man in Europe at the time.
It was only after he was spotted loitering outside a closed station at 3am that he was approached by a rookie police officer and opened fire, before being shot dead.
Now Richard Walton, the former had of counter-terrorism at the Metropolitan Police, has warned the European Union must get tough on border control or risk encouraging even more atrocities.
He said: “Schengen poses a huge risk of terrorism, porous borders across mainland Europe are continuing to be exploited by Isil.
"They have a clear strategy and have set out to carry out attacks across mainland Europe.
“Europe's weakness is our weakness, it is a concern for us because if you're neighbours are insecure by definition.
"We need European countries to get their act together. Sooner or later they are going to get across the Channel."
Amri, now 24, claimed asylum in Italy in 2011 after fleeing Tunisia following a violent robbery and pretending to be a child migrant, despite being 19 at the time.
He was jailed for four years, although only served two, after a riot at his detention sent - but Italy was unable to deport him as Tunisia refused to take him back so he fled for Germany.
It has since been revealed the killer was under surveillance by German police after being overheard offering to carry out a "suicide attack".
The deadly attack earlier this week killed 12 people while dozens more injured, many still receiving treatment in hospital.
Now right-wing leaders have lead calls to scrap the Schengen Area, which enables passport free travel across the EU, over claims it is being “exploited” by Islamic State extremists.
Marie Le Pen, the leader of the French far-right National Front and presidential hopeful, said: "This escapade in at least two or three countries is symptomatic of the total security catastrophe that is the Schengen agreement."
Nigel Farage, Ukip’s former leader wrote on Twitter: “If the man shot in Milan is the Berlin killer, then the Schengen Area is proven to be a risk to public safety. It must go.”
And Iain Duncan Smith, a Tory MP and former Work and Pensions secretary, said that the case highlighted the need for Britain to leave the European Union "as soon as possible".
He said: "The sooner we get out the stronger our ability to look after ourselves and our borders will be.
"Where the European Union has been heading is towards this creation of a super state, within which there would be no borders, no controls, no checks. We are now beginning to see what a mistake that has been."
Last week it emerged that 200 undercover SAS soldiers had been placed on British streets to help police forces in case of terror attacks.
In Birmingham earlier this month, new road-block barriers were installed at the city's popular Christmas market.
Greater Manchester Police have also bolstered their numbers at local markets, which have almost 350 stalls spread across 10 sites.
Earlier this month, Northumbria police were spotted carrying assault rifles around Christmas markets to reassure public safety.
However, locals condemned the security measure as "terrifying," before adding that "we do not want armed police on our streets".
Mr Walton said "more bollards and troops on the streets is not the answer to this threat".
He added: "You have to build your intelligence capability more. You have to encourage people to come forward and you have to encourage the Muslim community to come forward and trust the agencies and report information and concerns they have got."