Migrant crisis Idomeni
Stranded migrants try to storm the Greek-Macedonian border, near the village of IdomeniReuters

Three-way clashes between police and different groups of migrants have broken out on the Greek-Macedonian border, where tensions have been running high after authorities allowed passage only to refugees of certain nationalities. Violence first erupted on 2 December, with police firing tear gas and rubber bullets at economic migrants that tried to stormed into Macedonia, breaking through freshly set-up border barriers.

The incident came as hundreds of people – mainly from Iran, Morocco and Pakistan – became stranded in the no-man's land between Greece and Macedonia after the latter changed its open border policy. Skopje decided to let through only would-be-refugees from the war-torn countries of Syria, Afghanistan and Iraq, pushing back everyone else.

On 3 December, migrants left out staged a protest at the Idomeni border area blocking off accesses to Macedonia to would-be-refugees. A makeshift 120-metre barrier made of empty barrels and pieces of wood was erected and scuffles erupted with people from both sides hurling rocks. At least two men were injured, while Greek riot police were deployed to separate rival factions.

Some exploited the chaos by looting food and water from a refugee camp nearby, while a man died from electrocution after touching a high-power overhead railway cable. The man, said to be Moroccan, had climbed atop a stationary train carriage. Another Moroccan national was severely burned in a similar accident last week.

Skopje had allowed in all migrants on their way to central and northern Europe throughout the summer. Starting in late November, the government decided to restrict access out of fear that economic migrants would remain stuck in Macedonia, after countries to its north voiced they were to clamp down on non-refugees.

The move triggered immediate protests, with some Iranian refugees sewing their lips shut and going on hunger strike. "Why aren't they allowing us to cross?" Eli, a 30-year-old Pakistani who has been living in Greece for six years but wants to relocate to Germany, told AP. "We're waiting until they open [the border]. Why is there this discrimination going on? The border must either open for all or closed for all."

Greek authorities have offered to transport migrants back to Athens via train. They said more than 5,500 people, including about 2,500 refugees and 3,000 migrants, are currently stationed in the Idomeni border area.