French fighter planes have fired at rebels in northern Central African Republic (CAR) where thousands have fled fighting in recent weeks.

French Mirages attacked rebel positions in Ouadda and N'Dele in support of government forces.

A rebel spokesman told the BBC that five of his fighters had been killed. It is the second time this week that French forces have fought the rebels.

The UN has warned CAR's conflict is linked with fighting in Chad and Sudan.

CAR shares its northern borders with the two countries, which have been plagued by insecurity since trouble erupted in Sudan's western Darfur region in 2003.

Earlier this month, France promised to provide logistics and intelligence to CAR in their struggle against rebels who have recently seized several towns.

The government says the Union of Democratic Forces for Unity (UFDR) rebels are operating from Darfur with the support of the Sudanese authorities.

The BBC's Joseph Benamse in Bangui says France recently added 100 troops to its 200 soldiers stationed in CAR.

Under bilateral accords, France's military provides logistical and intelligence support to some of its former colonies in Africa.

The UFDR rebels say they are fighting against corruption and mismanagement under President Francois Bozize, who seized power in a 2003 coup.