Islamist rebels, who infiltrated and attacked the northern Malian town of Gao Saturday, were repelled after two hours of fierce fighting, Malian army officials said.

Insurgents had slipped past army checkpoints to enter the town, prompting Gao residents to raise an alarm, Malian army officials told news agencies.

Gao Mayor Sadou Diallo said the Islamist fighters had launched the attack inside the city's Quatrieme Quartier, or Fourth District, and retreated when they were engaged by Malian forces.

"There was heavy gunfire. The situation is under control now. The Islamists entered via Quatrieme Quartier, and the army went to meet them and was able to push them back," Diallo told the Associated Press news agency.

"There is another group that entered via the river, but they too were pushed back. It's under control,” Diallo said.

Details regarding casualties have not been made public.

Gao was the first town to be attacked by a retaliatory suicide bomber Feb. 8. Since the first case of suicide bombing in Gao there have been several similar attacks in other northern cities.

France deployed troops in Mali, Jan. 11, to contain the expansion of Al-Qaeda-linked fighters who had established strongholds in northern Mali since March last year and had been posing a threat to Bamako, the capital.

The French-led troops recaptured the Islamist strongholds Gao, Timbuktu and Kidal by January end with virtually no combat or casualties, raising concern that the insurgents who were forced out of the region’s main towns may resort to guerilla warfare to strike back.

The Movement for Oneness and Jihad in West Africa (MUJAO), one of the Al-Qaeda-linked groups, had been in control of northern Mali for 10 months following a military coup in March 2012. MUJAO had claimed responsibility for the Feb. 8 suicide bombing.

France now has more than 4,000 troops on the ground in the country, including 1,200 deployed in the northeast, carrying out clean-up operations after a successful crackdown on the Islamist rebels.

Western nations fear that the insurgents, with the support from Al-Qaeda in the Islamic Maghreb (AQIM), could use Mali as a base for unleashing terror on the West and expanding the influence of Islamist militants in Yemen, Somalia and North Africa.