A bomb struck a vehicle in Algeria and killed five people, media reported on Wednesday, in the deadliest attack in months as the country battles violence blamed on Islamist militants.

Three of the people killed in Tuesday's blast were from the same family, local media reported.

There was no claim of responsibility for the attack, which struck close to Djelfa, about 270 kilometres (170 miles) south of the capital Algiers.

The previous most deadly incident was in October last year when five soldiers were killed in an attack blamed on Islamist militants in the eastern Kabylie area, where Islamists fighters have established their headquarters.

Ten more soldiers were wounded when militants attacked soldiers hunting down Islamist fighters, first detonating a remote-controlled bomb and then opening fire with automatic weapons, according to media accounts.

The soldiers had been looking for members of the former Salafist Group for the Preaching and Combat (GSPC), a group which formed an alliance with Al-Qaeda.

The Algerian army launched on September 23 a massive sweep against the Islamists, with Al-Qaeda in the Islamic Maghreb (AQIM) increasingly active in North Africa. The group grew out of the GSPC.

Several newspapers also reported Wednesday that the Algerian army killed a local AQIM chief, Mourad Bouher, late Monday.

Violence linked to Islamist militant groups dropped off over the past five years in Algeria, after hitting the North African country hard for two decades.

Its protracted war with Islamist militants in the 1990s resulted in some 200,000 deaths and the imposition of a state of emergency in 1992.

Emergency rule was repealed on February 24 following unprecedented protests that threatened President Abdelaziz Bouteflika's decades-old regime, against a background of revolts across the Arab world.

The lifting of martial law, which gave free rein to security forces that effectively served to repress political freedom, was a key demand of the unprecedented protests, which led to clashes that left five people dead.

Washington warned Algiers last week that AQIM may exploit the unprecedented unrest and violence that have been roiling the region, with waves of protests in Tunisia and Egypt toppling their long-time rulers this year.

" I don't think we should expect terrorists to stand by and it is an opportunity for them to gain ground," State Department coordinator for counter-terrorism Daniel Benjamin said Friday on a visit to Algiers.