Eight Algerian soldiers were reported killed and three injured, when their convoy was ambushed by suspected Islamic militants on Tuesday.
The conflict with Islamists has taken a huge toll
The militants detonated explosives as the convoy drove through mountains towards Montgorno, 90 kilometres (55 miles) south of Algiers, and then opened fire.
Nine soldiers died in a similar incident west of the capital a fortnight ago.
About 150 extremists have been killed in army operations in the past two weeks, according to press reports, in continuing civil unrest which has left over 120,000 dead in the past 11 years.
There are two main Islamic groups, the GIA and the GSPC, who have been fighting the government since elections were cancelled in 1992, on the eve of victory for the fundamentalist Islamic Salvation Front.
That party has now been disbanded.
Press reports say that the rebels in the latest attack fired on the army convoy with machine guns.
They seized the weapons that were being carried by the convoy.
The GIA are reported to be active in the area where the ambush took place, and also around Ain Defla, 140km (85 miles) west of Algiers, where the earlier ambush took place.
In a separate incident, GSPC fighters were reported to have slit the throats of four people who wanted to surrender to soldiers in the Babors mountains, 300km (180 miles) east of Algiers.
The GSPC were reportedly the 150 victims of the army operation in the inaccessible Babors mountains, where the group was holding a meeting.
One report spoke of 105 charred bodies being found in a cave.