As part of a NATO peacekeeping mission being reinforced, British troops are patrolling the Kosovo-Serbia border out of worry that the former adversaries could resume hostilities after a string of violent incidents in recent months.

Following a conflict between the government and armed Serbs holed up in a monastery on September 24, which converted a peaceful town in northern Kosovo into a war zone, the North Atlantic Treaty Organization dispatched hundreds of more forces to Kosovo from Britain and Romania.

One police officer and three gunmen were killed in the village of Banjska in what was seen as the worst violence since Kosovo declared independence from Serbia in 2008.

Kosovo accused Serbia of providing financial and practical support for the gunmen, which Belgrade denies.

NATO has sent 1,000 extra troops to the region, bringing its presence there to 4,500 peacekeepers from 27 countries.

British soldiers are now being deployed in 18-hour shifts in freezing conditions to make sure no weapons or armed groups enter Kosovo.

“Currently we are here on a routine patrol, which consists of understanding patterns of life, gaining intelligence on any illegal or suspicious activity that then gets fed back to KFOR (NATO mission) and higher,” Lieutenant Joss Gaddie from the British Army told Reuters at the border with Serbia.