BAMAKO, Mali (AFP) — French and Malian troops yesterday advanced on the key Islamist stronghold of Gao after recapturing the northern town of Hombori as the extremists bombed a strategic bridge to thwart a new front planned in the east.

The French-led assault against the radical Islamists controlling northern Mali entered its third week with a strong push into the vast semi-arid zone amid rising humanitarian concerns for people in the area facing a dire food crisis.

“At present, Malian and French soldiers are in Hombori. There are no longer any Islamists on the ground,” said a teacher in the town which lies 575 miles north of the capital Bamako.

A Malian security source said the troops would press on to Gao, one of the three major northern towns along with Kidal and Timbuktu, where the Al Qaeda-linked Islamists have imposed brutal sharia for 10 months.

The security source added that in the west, the 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” which lies further north.

Gao, Timbuktu and Kidal were seized by an alliance of Tuareg rebels — who wanted to declare independence of the north — and hardline Islamist groups in April last year.

The Islamists hijacked the rebellion and sidelined the Tuaregs to implement radical Islamic laws, flogging, stoning and executing transgressors, forbidding music and television and forcing women to wear veils.

France swept to the aid of the weakened Malian army on January 11 as the Islamists pushed south towards the capital Bamako. They bombarded both Gao and Timbuktu with airstrikes, sending the Islamists fleeing.

However the insurgents remained on the offensive, blowing up a key bridge linking Gao to neighbouring Niger yesterday, where more than 2,000 Chadian soldiers and 500 troops from Niger are being deployed to open a second front against the Islamists from the east.

“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.

Aid groups warned of rising food insecurity as fighting escalated in the drought-wracked Sahel.

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,” a statement said.

There has also been increasing alarm about reports of rights abuses by Malian soldiers against ethnic Tuaregs and Arabs.

The International Federation of Human Rights Leagues said at least 31 people had been executed in the central town of Sevare, and some bodies dumped in wells, according to local researchers.

Medecins Sans Frontieres said it had gained access to towns retaken from Islamists like Konna in the centre, where it sent a four-member medical team.

Meanwhile, West African defence chiefs planned to review progress on the limping deployment of their forces to Mali at an emergency meeting in Ivory Coast on Saturday.

The Economic Community of West African States has pledged more than 4,500 soldiers to help Mali retake its Islamist-occupied north, but the deployment has been delayed by financing and logistical problems.

Britain, which has already contributed two C-17 transport planes to airlift military equipment, sent a surveillance plane to aid operations, according to the Ministry of Defence.

France has asked several Western countries and others to support logistics, including planes to allow aerial refuelling, sources close to Defence Minister Jean-Yves Le Drian said.