Ground forces backed by French paratroopers in Mali prepare to capture Timbuktu after taking control of airports and roads

Fall of Timbuktu will mark the end of an initial, lightning advance by French and Malian forces into territory overrun by Islamists

French and Malian forces today surrounded the ancient desert town of Timbuktu, leaving only one large settlement in Mali in the grip of islamist rebels.

The fall of Timbuktu, a world heritage site and legendary destination since the middle ages, will mark the end of an initial, lightning advance by French and Malian forces into territory overrun by the Islamists. Many of the rebels are believed to have retreated to their last bastion, Kiddal, in the mountainous north east of Mali, close to the Algerian border.

A French military spokesman said this morning that Malian troops would lead the advance into Timbuktu later today. It was unclear how many Islamist fighters remained in the town.

Reports are emerging from Timbuktu of the summary execution by lslamists of at last one young man who celebrated the French-led advance. There have also been reports of the burning by Islamists of some of the 20,000 ancient Islamic manuscripts which have been preserved in Timbuktu since the middle ages.

French and Malian ground forces backed by French paratroopers and helicopters seized the airport and all roads leading to town overnight. A similar operation preceded the fall of Gao (population 60,000), the largest town held by rebels, on Saturday.

Colonel Thierry Burkhard, spokesman for the French chiefs of staff, said today that the Timbuktu airport was captured without resistance. “There was an operation on Timbuktu last night that allowed us to control access to the town,” he said. “It's now up to Malian forces to retake the town.”

The rapid advance by French and Malian forces since the middle of last week means that almost all the Niger river valley – the most populous part of northern Mali – has been recaptured from the rebel groups who overran the immense, northern part of the country last year. Defence sources in Paris say that the 2,500 French troops will pause before moving on towards the last Islamist bastions in the far north east.

As it enters its third week, French sources are delighted by the relative smoothness of their operation to help the Malian government to defeat|the rebels. They have warned, however, that the conflict may soon enter a hit-and-run guerrilla phase.

During their occupation of Timbuktu since last summer, the Islamist militants are reported to have destroyed some of the UNESCO World Heritage sites, including the tombs of Sufi saints. According to the fundamentalist interpretation of of Islam, the tombs are heretical because they encourage Muslims to worship saints rather than God.