Sixteen people, including a baby aged seven months, were murdered by armed attackers at their village south of Algiers, the daily Le Soir d'Algerie reported yesterday, as 15,000 people marched in Algiers alleging fraud in elections held last week.
The newspaper report said four men and a woman were also kidnapped from the village of Oued Djer during the attack late on Friday.
It said the casualties included 10 children, among them the baby, who was mutilated.
It was the first massacre since last week's widely contested municipal polls in which the pro-government National Democratic Rally (RND) claimed a landslide victory.
A separate report yesterday said Algerian security forces have uncovered a mass grave at the bottom of a well in the Bentalah region near Algiers. The well could contain more than 30 bodies of victims massacred by Islamic extremists last month, the daily Liberte paper reported.
Elsewhere seven civilians, including six members of one family, were killed since Sunday in the continuing violence gripping the country. On Sunday a bomb was defused in a mosque at Ketchua in the Basse Casbah old town, press reports said.
The mass grave in Bentalah was found at the bottom of a 40metre-deep well in a pasture.
People who had escaped last month's massacre there said more than 200 were killed, but the official toll remains at 85.
"About 30 cadavers, maybe more, were thrown down there," said the Liberte report. "Some sources said these were believed to be women kidnapped during the killings at Rais or Bentalha."
The efforts of fire personnel to recover the bodies were thwarted because of decomposition.
Press reports said six civilians had their throats cut on Saturday night in Taoudmout in the Saida region of south-western Algeria, and a 14-year-old managed to escape.
In Algiers on Saturday night the brother of a candidate of the opposition Socialist Forces Front (FFS), Mr Abdelkrim Haddad, was shot dead in front of his home by a weapon with a silencer, Liberte said.
It said security forces on Saturday killed an armed Islamic fundamentalist in the village of Cherarba on the outskirts of Algiers, where bomb-making materials were found.
Yesterday an estimated 15,000 people, mainly supporters of secularism, demonstrated in Algiers, protesting against "massive fraud" in last Thursday's municipal elections.
The march, organised by the opposition FFS, was supported by activists from three other parties, including the National Liberation Front (FLN) and the Islamist Movement of Society for Peace (MSP), which are both members of the ruling coalition.
Thousands of people crammed on to balconies along the main streets of Algiers to cheer the demonstration, which was closely monitored by the security forces, witnesses told Reuters by telephone.
Demonstrators shouted "cheats" and "thieves", as well as "we want peace", as they walked from May 1st Square to Martyrs' Square in the centre of Algiers.
The event was said to have passed off peacefully.
FFS leaders called for demonstrations to continue and for activists to take part in marches led by other groups.
The RND, allied to President Liamine Zeroual, won most of the seats in the elections, provoking the strong protests from other parties.