The papers Liberte, El Watan and El Khabar said the eight, including an officer, were ambushed in wooded mountains while on a patrol in the Ain Defla region 120 km (75 miles) south-west of Algiers on Thursday.
It was the largest reported single loss of state personnel to politically-motivated fighting since Islamist guerrillas killed 13 customs agents in the desert south in April.
Liberte and Khabar said they believed the attack was carried out by the main rebel group, the Salafist Group for Preaching and Combat (GSPC), which has consistently rejected peace overtures from the government and announced in September it had joined al Qaeda.
The army declined immediate comment. It does not normally comment on security matters.
The newspapers said the attackers, estimated to number up to 30, took the arms and uniforms of the dead soldiers and fled.
For years rebels trying to set up an Islamic state have set up false roadblocks wearing army or police uniforms to carry out attacks on travellers.
Algeria descended into violence in 1992 when Islamists staged a rebellion after the then military-backed authorities, fearing an Iranian-style revolution, scrapped a parliamentary election that Islamist radicals were set to win.
Up to 200,000 people are estimated to have been killed in the fighting. The violence has sharply declined in recent years.
The newspapers reported that Islamist Web sites published a statement purporting to come from the GSPC that claimed responsibility for simultaneous truck bomb attacks on police stations near Algiers during the night of Oct. 29.
The bombings, the most elaborate assault by Islamist rebels in several years, killed three people, all civilians, and wounded 24, according to the police.
The alleged GSPC statement said at least 30 policemen were killed or wounded in the bombings.
"The latest explosions constitute one message: we will continue the jihad and we will never abandon it," said the alleged GSPC statement, dated Oct. 31.

Copyright Reuters, 2006