A car bomb exploded near a police station in a town east of Algiers today, wounding 25 people including four policemen, the government said.
The blast happened at about 5am (04.00 GMT) in Tizi Ouzou, the main town in the mountainous Berber-speaking Kabylie region of northern Algeria, Interior Minister Noureddine Yazid Zerhouni was reported as saying by the official APS news agency.
A previous official toll said 21 people including six policemen had been wounded.
The explosion dug a big crater in the road beside the police station and damaged nearby buildings. Private news websites described the blast as having been caused by a suicide bomber. There was no immediate confirmation of that.
There was also no immediate claim of responsibility. Similar attacks have been claimed by a group which calls itself al Qaeda in the Islamic Maghreb and has its main base in Kabylie.
One of these attacks included twin suicide bombings of UN offices and a court building in Algiers in December 2007, killing 41 people, 17 of them United Nations staff.
Mr Zerhouni and national police chief Ali Tounsi inspected the blast site in Tizi Ouzou and visited the wounded in hospital. Mr Zerhouni said local authorities had been instructed to temporarily rehouse 15 families whose apartments had been damaged.
He urged citizens to be vigilant "to thwart the designs of the terrorists, who want to undermine the efforts of the State to reinforce security across the country", APS said.
Algeria is emerging from more than a decade of conflict that began when in 1992 the military-backed government scrapped legislative elections a radical Islamic party was poised to win. About 150,000 people have died during the ensuing violence.
The bloodshed has subsided in recent years and in 2006 the government freed more than 2,000 former Islamist guerrillas under an amnesty designed to put an end to the conflict.
But a hard core of several hundred rebels fights on in Kabylie as members of al Qaeda's North Africa wing, which was previously known as the Salafist Group for Preaching and Combat or GSPC.
Several small al-Qaida-linked groups are also active in the Saharan south and are believed to have ties to criminal smuggling networks.
Reuters