Far-Right extremists yelling "Burn them alive" launched a violent attack overnight on migrants staging a sit-in protest on the Greek island of Lesbos, injuring around a dozen people.

The violence erupted late on Sunday after members of the radical Patriotic Movement gathered on the central square of the island's main city Mytilene, where around 200 Afghan asylum-seekers held a sit-in protest against their miserable living conditions.

Despite a police presence, the situation soon escalated as the extremists started throwing bottles and lighting flares, shouting slogans like "Burn them alive" and "Throw them in the sea".

Tensions spiraled further when Left-wing activists arrived in support of the migrants and started fighting with the far-Right supporters.

The clashes raged all night until security forces used tear gas to disperse the crowd and evacuate the square, forcing the Afghans to return to the island's overcrowded migrant camps.