GAO, Mali -- French and Malian troops on Monday sealed off Timbuktu, a UNESCO World Heritage site, but fleeing Islamist rebel fighters torched several buildings in the ancient Saharan trading town, including a library of priceless manuscripts.

Without a shot being fired to stop them, 1,000 French soldiers including paratroopers and 200 Malian troops seized the airport and surrounded the centuries-old Niger River city, looking to block the escape of al-Qaida-allied fighters.

The retaking of Timbuktu followed the swift capture by French and Malian forces at the weekend of Gao, another major northern Malian town which had also been occupied by the alliance of Islamist militant groups since last year.

A two-week intervention by France in its former Sahel colony, at the request of Mali's government but also with wide international backing, has driven the Islamist rebel fighters northwards out of towns into the desert and mountains.

A French military spokesman said the assault forces at Timbuktu were being careful to avoid combat inside the city so as not to damage cultural treasures and mosques and religious shrines in what is considered a seat of Islamic learning.

But Timbuktu's mayor, Ousmane Halle, reported that fleeing Islamist fighters had torched a South African-funded library in the city containing thousands of priceless manuscripts.

Nic Bothma / EPA

A French soldier in Mali on Sunday.

"The rebels set fire to the newly constructed Ahmed Baba Institute built by the South Africans ... this happened four days ago," Halle Ousmane told Reuters by telephone from Bamako. He said he had received the information from his chief of communications who had traveled south from the city a day ago.

Ousmane was not able to immediately say how much the concrete building had been damaged. He added the rebels also torched his office and the home of a member of parliament.

The Ahmed Baba Institute, one of several libraries and collections in the city containing fragile ancient documents dating back to the 13th century, is named after a Timbuktu-born contemporary of William Shakespeare and houses more than 20,000 scholarly manuscripts. Some were stored in underground vaults.

'Free as the wind'
The French and Malians have faced no resistance so far at Timbuktu, but they face a tough job of combing through the labyrinth of ancient mosques and monuments and mud-brick homes between alleys to flush out any hiding Islamist fighters.

"We have to be extremely careful. But in general terms, the necessary elements are in place to take control," French army spokesman Lieutenant Thierry Burkhard said in Paris.

Timbuktu member of parliament El Hadj Baba Haïdara told Reuters in Bamako the Islamist rebels had abandoned the city. "They all fled. Before their departure they destroyed some buildings, including private homes," he said.

The United States and European Union are backing the French-led Mali operation as a strike against the threat of radical Islamist jihadists using the West African state's inhospitable Sahara Desert as a launch pad for international attacks.

They are helping with intelligence, airlift of troops, refueling of planes and logistics, but do not plan to send combat troops to Mali. 

In Gao, crowds celebrated the arrival of French forces. Many smoked cigarettes, women went unveiled and some men wore shorts to flout the severe Shariah Islamic law the rebels had imposed for months. Youths on motorcycles flew the flags of Mali, France and Niger, whose troops also helped secure the ancient town on the Niger River.

"Now we can breathe freely," said Hawa Toure, 25, wearing a colorful traditional African robe banned under Shariah for being too revealing. "We are as free as the wind today. We thank all of our friends around the world who helped us," she said.

About a dozen rebels were killed in Gao, while French forces suffered no losses or injuries, the French defense ministry said.

Youths in Gao said there were still some rebels and rebel sympathizers around, but they were being found. "Yesterday, even, we found one hiding in a house. We cut his throat," one man said, asking not to be named. "Today we found another and we brought him to the army."

A third northern town, the Tuareg seat of Kidal, in Mali's rugged and remote northeast, remains in rebel hands.

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