An Al-Qaeda splinter group claimed Saturday to have carried out a suicide attack on a police base in southern Algeria which left 23 people wounded according to the defence ministry.

"We inform you that we are behind the explosion that occurred this morning at Tamanrasset," a message sent to AFP and signed by the Movement for Oneness and Jihad in West Africa said.

"The explosion caused serious material damage to the building located on the main street of Tamanrasset as well as nearby homes," the Algerian defence ministry said in a statement, carried by the national news agency APS.

"Four gendarmes are under medical observation," it said. The gendarmerie said 15 gendarmes, five members of the civil protection organisation and three passers-by were taken to hospital.

The gendarmerie said "a terrorist" driving a Toyota 4x4 targeted the main entrance of the base in Tamanrasset, 1,970 kilometres (1,220 miles) south of Algiers at 7:45 am (0645 GMT) Saturday.

The website of the Algerian Arabic-language daily En Nahar said the bomber was blown apart in the blast. It was the first time such an attack had been reported in the area.

The Movement for Oneness and Jihad in West Africa (Jamat Tawhid Wal Jihad Fi Garbi Afriqqiya) surfaced in December, when it claimed to be holding three Westerners kidnapped from a Western Sahara refugee camp in Algeria in October.

Security sources said it had broken off from the main group, Al-Qaeda in the Islamic Maghreb (AQIM), in order to spread jihad to west Africa and not confine themselves just to the Maghreb or Sahel regions.

The group released a video of the abducted aid workers and another showing six dark-skinned, turbaned men speaking of their ideological references, including Al-Qaeda founder Osama bin Laden and Taliban leader Mullah Omar but putting more emphasis on historical figures of west African Islam.

Also in December, Mali and Algeria agreed to step up coordination in efforts to root out Al-Qaeda-linked groups in the region.

Al-Qaeda-linked groups have been active in Algeria, Mali, Niger and Mauritania for a decade but their activity has picked up since the fall of Moamer Kadhafi scattered the slain Libyan strongman's arsenal across the region.

In April 2010, the four countries formed a Committee of Joint Chiefs (CEMOC), based in Tamanrasset, a garrison town near the border with Mali and Niger, to coordinate their military efforts against AQIM.

On Saturday, a source close to mediators trying to secure the release of an Italian and two Spanish aid workers kidnapped in October said the Movement for Oneness and Jihad wanted 30 million euros ($39 million) for their release.