Nouakchott, Mauritania  - Mauritanian security forces Tuesday launched grenades on a house where Islamist radicals had escaped to after clashing with police and soldiers on Monday, the local news agency ANI reported.

The extremists had, however, fled before police arrived at the house in the north of the capital Nouakchott.

The attack on the house followed street clashes in which one Islamist and one police officer were killed and at least eight people, most of them members of of the security forces, were injured.

Police managed to capture an injured person believed to be Sidi Ould Sidna, one of among three people suspected of shooting and killing four French tourists in December.

One of the three suspects is still at large.

Ould Sidna was extradited to Mauritania from Guinea-Bissau where he had fled, but escaped from a Nouakchott law court last week.

Mauritania blames the killing of the French tourists on al-Qaeda- linked Islamists.

The north-west African desert country has seen little terrorism so far. Increasing security concerns led to the cancellation of the Lisbon-Dakar rally, which was due to pass through Mauritania in January. (dpa)