There have been the direct clashes between Sunni and Shi’ite Muslims in Bahrain for the first time since anti-government protests began there two weeks ago.
Wielding what looked like baseball bats, around 100 people were involved in the violence in Hamad Town.
Ambulances were seen rushing from the scene as helicopters circled overhead.
The clashes contrast with the protests in the capital where crowds have been careful to avoid sectarianism.
But the Shi’ite majority has long complained of second class status in a country ruled by Sunnis.
The latest unrest comes as Bahraini opposition agreed to enter talks with the government.