Migrants, police clash in Bulgaria refugee camp

Some 1,500 migrants rioted on Thursday in Bulgaria's largest refugee camp, triggering clashes that injured several police officers and prompted the arrest of 40 protesters, officials said.

Between four and six officers were injured in clashes that saw police use water cannon and riot guns to disperse protesting migrants at the Harmanli reception centre near the Turkish border, the interior ministry's chief of staff Georgy Kostov told Nova television.

Angry migrants -- mostly Afghan -- set car tyres on fire and threw stones at some 250 police officers and firefighters at Harmanli earlier Thursday to protest a recently imposed ban on the migrants to leave the centre pending medical checks.

Local police chief Nina Nikolova told AFP in the early afternoon that the situation was under control and that the migrants were in talks with the state refugee agency.

But tensions flared up again in the evening.

The centre, which houses just over 3,000 migrants, was the scene of another protest in October when several hundred Afghans demanded they be allowed to continue their journey towards western Europe.

With a fence on the Turkish border, Bulgaria has largely remained on the sidelines of Europe's worst migration crisis since 1945, which unfolded last year.

Nonetheless some 13,000 migrants, mostly from Afghanistan, are currently trapped in the European Union's poorest country.

Although the so-called Balkan migrant trail was effectively shut down in March, migrants have continued to cross the region in smaller numbers.

Tensions have been rising particularly in Greece where tens of thousands of people remain stranded.

Neo-Nazis launched last week attacked a migrant camp on the eastern Greek island of Chios.

A number of people were injured in the violence, which also left dozens of refugees stranded without a tent.