Rebels have attacked a village in eastern Syria, killing dozens of Shia Muslim residents, activists say.

The UK-based Syrian Observatory for Human Rights (SOHR) said at least 60 people, mostly pro-government fighters, died in Hatla on Tuesday.

The attack appeared to be retaliation for an attack on a rebel position by people from the village, which is predominantly Sunni, the group added.

Those Shia residents who survived the rebel attack are reported to have fled.

The two-year-old conflict in Syria is turning increasingly sectarian, pitting rebels who are mostly from the majority Sunni community against government forces led by President Bashar al-Assad's Alawite sect, a heterodox offshoot of Shia Islam.