Around a dozen people, including two policemen, were wounded Friday in fresh clashes between Arabs and Berbers near the southern Algerian town of Ghardaia, a medical source said Al Arabiya reported.
The unrest erupted after the main Friday prayers outside a mosque in Berriane, 45 kilometres (28 miles) north of Ghardaia, APS news agency quoted the source as saying.
The two sides threw Molotov cocktails and rocks at one another and caused a major backup on a key highway linking the country's north and south before police dispersed them with tear gas, the source said.
Some businesses and homes in the area were looted, the source added.
Ghardaia has been the scene of ethnic violence that has killed seven people and wounded more than 400 since December when fighting erupted between Berbers, known as Mozabites, and Arabs, known as Chaambas.
Hundreds of houses and shops in the town, which is a UNESCO heritage site, have also been burned down in the unrest.
The two communities have lived together for centuries, but tensions between them have risen sharply since vandals destroyed a historic Berber shrine in late December.
Videos shown to visiting journalists in January have been circulating on the Internet showing youths vandalising Mozabite property and smashing up the tomb of Amir Moussa, a 16th century Berber leader, and desecrating the ancient cemetery in Ghardaia, as police look on.