French jets have bombed rebel positions as well as fuel stores and ammunition dumps near their Gao stronghold after capturing the town of Hombori in northern Mali.
"At present, Malian and French soldiers are in Hombori," said a teacher on Friday in the town, which lies 920km north of the capital Bamako and 200km west of Gao. "There are no longer any Islamists on the ground."
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Allied forces are pushing ahead to Kidal and Timbuktu, where an alliance of Tuareg fighters and al-Qaeda-linked rebels seized the town back in April.
To the west, the source added, French-led forces who had recaptured the town of Diabaly on Monday were pushing towards the town of Lere with the aim of "taking control of Timbuktu" further north.
Gao, Timbuktu and Kidal were seized by an alliance of Tuareg rebels and Islamist groups last year. The Islamists hijacked the rebellion and sidelined the Tuaregs.
But as the French-led assault against the rebels controlling northern Mali entered its third week, aid workers have warned about a growing food crisis for civilians.
Hundreds of thousands of Malians, mainly Tuaregs, are escaping rebel-held areas in the north fearing a backlash.
Refugees have been fleeing to the Malian-Mauritanian border, and the UN expects as many as 700,000 civilians will be displaced by the fighting.
Bridge blown up
France swept to the aid of the weakened Malian army on January 11, as the rebels pushed south towards the capital Bamako.
On Friday, however, the rebels blew up a strategic bridge at Tassiga, which would have given African troops gathering in Niger to the south easy access to Gao.
Meanwhile, more than than 2,000 Chadian soldiers have arrived in Niger, joining 500 soldiers from the country's army, to tackle the rebels by opening a second front against them.
"The Islamists dynamited the Tassiga bridge. No one can pass to Niger or come to Gao," said the owner of a transport business, Abdou Maiga. A security source from Niger confirmed the strike, according to the AFP news agency.
Aid groups have warned of rising food insecurity as fighting escalated in the drought-wracked Sahel.
| Al Jazeera reports from Mali's frontlines
A statement from French aid group Action Against Hunger (ACF) raised fears "that an armed ground intervention from Niger will cut the last access route to supply basic goods (food and medicine) to people in the region".
And a day after rights groups expressed concern about reports of executions of ethnic Tuaregs and Arabs carried out by soldiers of Mali's army, fresh evidence emerged of killings carried out by the rebels.
Melissa Fleming, a spokeswoman for the United Nations refugee agency, said one person who had fled the city of Gao described seeing "a woman being executed summarily for refusing to show the contents of her bag to a rebel fighter as she tried to board a bus".
Mali's military spokesman has said that they will investigate the matter.
Meanwhile, US president Barack Obama has backed France's military intervention during a telephone conversation with the French president Francois Hollande.
In the Ethiopian capital Addis Ababa, the African Union said it would be calling on its members to bolster the strength of AFISMA, the African-led force for Mali.
The AU would also seek support from the United Nations for the operation, in the form of transport, medicine and field hospitals, peace and security commissioner Ramtane Lamamra told reporters.
West African defence chiefs plan to review progress on the slow deployment of their forces to Mali at an emergency meeting in Abidjan, the capital of Ivory Coast, on Saturday.
Source: Al Jazeera and agencies