Seven people were killed in a second day of fighting between rebels and Malian and French forces in the northern Malian town of Gao, authorities said.



The rebels attacked the north's largest town on Sunday just days after French President Francois Hollande said Mali's sovereignty had almost been restored.

Earlier, Mali's army repulsed an attack by a group of rebels who had slipped past army checkpoints to enter the northern town of Gao, a military official says.



The Malian army official said that government forces defeated the rebels on Saturday after more than two hours of intense fighting.



The clashes took place after Gao residents reported rebels had entered their neighbourhood.



Gao was controlled for almost 10 months months by the Movement for the Oneness of Jihad in West Africa (MUJAO), which imposed a violent form of sharia, until the town was liberated by a French-led offensive in late January.



It was the third major attack on Gao since it was liberated.



The assault indicates that MUJAO remains entrenched and able to attack despite the thousands of French troops who have liberated most of northern Mali's towns from control by the rebels.



Gao Mayor Sadou Diallo said earlier that the rebel fighters launched their attack inside the Quatrieme Quartier, or Fourth District, a neighbourhood inside the city which is divided into a numbered grid.

'Heavy gunfire'



The mayor said that Malian forces engaged the fighters and they retreated, but a second column of rebels then attacked from across the Niger River.



"There was heavy gunfire," Diallo said. "The situation is under control now."



However, residents said that they still heard shooting.



MUJAO amputated the limbs of so many accused thieves during its rule that the public place where they meted out their version of justice became known as "Shariah Square".



The city, along with much of the rest of northern Mali, was liberated in January by French troops, who used Mirage and Rafalle jets to bombard rebel positions then launched a ground assault.



Gao was the first town to be attacked by a suicide bomber on February 8.



That style of attack was previously unknown in Mali, but it has since been repeated in several other northern cities.



Rebels attacked the city twice in February.



Extra French troops have been brought in to reinforce the city's defences, but the frequency of the attacks has many worried that extremism has taken root in Gao's soil.