Deadly floods are rare in Ghardaia
Flash floods have killed at least 29 people in Ghardaia, an Algerian oasis town in the Sahara and a UN World Heritage site, officials say.
Ali Belkhir, the head of public health at the health ministry, said a further 84 people had been injured.
Interior Minister Noureddine Yazid Zerhouni earlier told the official APS news agency that up to 600 homes had been inundated.
The rains, which began on Tuesday, have cut gas and electricity in Ghardaia.
The authorities say they have saved numerous people by helicopter and are helping those who are injured.
Ghardaia is one of several fortified Berber medieval settlements about 600 kilometres (375 miles) south of the capital, Algiers.
Mr Zerhouni also said food stocks in the town - home to around 100,000 people - had been flooded and probably made unfit to eat.
Ghardaia is listed as a UN World Heritage site
Ghardaia is the M'Zab valley, along a river bed which is dry most of the year and is listed as a UN World Heritage Site and frequented by European tourists.
Algeria has been hit by several floods in recent years.
A 48-hour deluge in the north of the country in 2001 killed at least 700 people and injured hundreds more.
But deadly floods are rare in Ghardaia.
Located at the edge of Algeria's desert, the town has a network of irrigation channels dating back centuries that distributes scarce seasonal rainfall.
This week floods have caused problems elsewhere in North Africa.
The Moroccan state press agency said two people were killed and one is still missing following torrential rains in the region of Marrakech.