Intelligence services are monitoring Balkan migration routes amid fears they are being used by foreign fighters fleeing from the Islamic State jihadist group's former territories in Iraq and Syria, Italy's chief of police Franco Gabrielli said on Friday.
"Migrant flows in the Balkans are under surveillance...we have indications that they may and in some cases probably do contain foreign fighters," Gabrielli told a meeting of Balkan police chiefs in Rome.
"We are paying maximum attention," he said.
Since the fall in March of IS's five-year 'caliphate' in the Middle East, the possible movements of foreign fighters are under much closer scrutiny, he said.
The jihadists retain a presence in the region and are active in countries from Nigeria to the Philippines, according to intelligence agencies.