GAO, Mali (AFP) -- Five people, including two suicide bombers, died Friday in car bombings in northern Mali, a day after fierce urban battles between French-led forces and Islamists left up to 20 extremists dead, officials said.

Two vehicles targeting civilians and members of the ethnic Tuareg rebel group, the MNLA, exploded near the town of Tessalit, killing three and wounding several others, a security source said. The suicide bomber drivers also died.

A spokesman for the National Movement for the Liberation of Azawad (MNLA) in Burkina Faso confirmed the report. Mohamed Ibrahim Ag Asseleh said "the two kamikazes were killed and in our ranks there were three dead and four seriously wounded".

The blasts came after Al-Qaeda-linked rebels claimed a car bomb attack on Thursday near a camp occupied by French and Chadian troops in the city of Kidal, local officials said.

At least two civilians were reported wounded in that attack. The vehicle, apparently driven by a suicide bomber, was targeting the camp but exploded before it reached it, killing the driver, an official in Kidal governor's office said.

France sent in troops on January 11 to help the Malian army oust Islamist militants who last year captured the desert north of the country. Thousands of soldiers from African countries have also deployed since then and France plans to start withdrawing its troops next month.

But the French-led forces are increasingly facing guerrilla-style tactics after initially meeting little resistance in their drive to oust Islamists from the main northern centres of Gao, Kidal and Timbuktu.

The Tuareg MNLA blamed Friday's car bomb attacks on the Al-Qaeda-linked Movement for Oneness and Jihad in West Africa (MUJAO), one of Mali's main Islamist groups.

The MUJAO made no comment on the latest attacks, but on Thursday it told AFP that it was responsible for the car bomb in Kidal.

"More explosions will happen across our territory," MUJAO spokesman Abu Walid Sahraoui warned.

He also said the group had sent fighters to Gao, 1,200 kilometres from the capital Bamako, where battles with French-backed troops erupted overnight Wednesday after about 40 Islamists infiltrated the city.

The French military reported Friday that between 15 and 20 Islamists had died in the street clashes, mostly focused around the court house and the city hall, while two French troops received light injuries and four Malian soldiers were also thought to have been wounded.

More gunfire was heard in Gao on Friday, with Malian soldiers opening fire with rocket-propelled grenades on the city hall, killing at least one Islamist, according to Malian army colonel Mamadou Samake.

The bodies of four rebels were also found inside the building, he added.

A Malian soldier earlier said "many" bodies of dead fighters in the urban clashes wore explosives belts and that mines had been laid in the area, for which French deminers were called in.

MUJAO spokesman Sahraoui on Thursday said the rebels were determined to recapture the city: "Our troops have been ordered to attack. If the enemy is stronger, we'll pull back only to return stronger, until we liberate Gao."

A French legionnaire was killed on Tuesday in the mountainous Ifoghas region. The French military said that their "Panthere 4" operation in the Ifoghas had already left 30 Islamists dead since the start of the week.

Mali's Prime Minister Diango Cissoko said this week that large-scale military operations in the north were winding down, but sporadic fighting has continued.

The Red Cross said the clashes in Gao showed that unrest still plagued the region.

"The situation is not at all stable or calm," said Jean-Nicolas Marti, who heads the International Committee of the Red Cross mission in Mali and Niger.

The UN meanwhile said it had heard "horrifying reports" of human rights violations in northern Mali, echoing concerns by Human Rights Watch which has urged Bamako to act in the light of reports of serious abuses committed by Malian troops against light-skinned people, particularly Arabs and Tuaregs.

Ethnic Tuaregs in the north, who have long sought greater autonomy, initially backed the rebellion but later fell out with the Islamists and regained control of Kidal before the arrival of French troops.

Asked whether it was coordinating its efforts with the Tuaregs of the MNLA, the French military said Thursday it was working with "groups that have the same objective" as France.