By Adama Diarra

TIMBUKTU (Reuters) - Under a broiling midday sun, dozens of young men from Timbuktu in northern Mali dig with shovels and pails to clear a sand-choked well, in a desperate attempt to find water.

Once a tourist hotspot known for its holy sites and an annual music festival that only months ago drew U2 lead singer Bono, Timbuktu is now facing a growing humanitarian crisis since al Qaeda-linked gunmen took control.

A local-organized aid convoy, escorted by turbaned rebels on machine-gun mounted pickups, reached the desert town last week to help ease food, water and medical supply shortages.

That was the first outside help since rebels swept across Mali's north, taking advantage of the political chaos caused by a military coup in March.

"We preferred the liberty we enjoyed before to any humanitarian aid," said Moussa Traore, an unemployed resident, speaking to Reuters after the convoy arrived. He stayed in Timbuktu, his home town, instead of fleeing because he was hopeful for a swift end to the crisis.

Instead, he said, things have worsened. The black flags of the ruling rebel group, Ansar Dine, festoon buildings as its fighters, laden with ammunition belts and wearing headscarves to protect against the dust, patrol the streets.

Food, fuel, and water have grown scarce. Shops and banks have closed for fear of banditry, secular schools have turned into Koranic madrassas, and gunmen have destroyed the tomb of a Timbuktu saint they deemed un-Islamic.

While residents in Timbuktu declined to discuss alleged human rights abuses by Ansar Dine and other rebels, fearing retribution, Human Rights Watch and Amnesty International have accused fighters from Ansar Dine and other groups of killing, raping and looting.

Mali's desert has always been a hotbed of insecurity due to the government's lack of resources to patrol it, but the rebellion has complicated international efforts to restore order since the coup and raised western fears that al Qaeda will strengthen its foothold in the Sahara.

Violent protests have erupted against Islamist rule in other towns in northern Mali in recent weeks, including in Gao and Kidal, but demonstrations have so far been few and largely peaceful in Timbuktu.

GENERATORS, PUMPS SHUT DOWN

Since the central government lost control of the region after the March 22 coup, the trucks that normally supply fuel and other essentials to Timbuktu have stopped arriving, fearing banditry and rebel checkpoints. Most, if not all, international aid agencies are unable to work there.

As a result, the city's generators and diesel-driven water pumps have mostly stopped running, leaving residents scrambling for water by day and living in darkness by night.

"If necessary, we will use the river water," said one of the men helping to dig out a well, Hamidou Toure, referring to a polluted tributary of the Niger River some 18 km (11 miles) south of Timbuktu.

Many of the city's shops have also been boarded up for fear that roving gunmen will steal the goods inside.

"We lack absolutely everything," said a masonry worker in Timbuktu who asked not to be named. "Humanitarian aid is not the solution. If we don't return to democratic rule, the humanitarian aid will do nothing but strengthen the occupiers until they are strong enough to march on Bamako."

Regional block ECOWAS is leading talks aimed at restoring democracy in Mali within a year, after the coup by mutinous soldiers toppled President Amadou Toumani Toure and paved the way for the northern rebellion, initially led by Tuareg separatists using arms gleaned from Libya's war.

ECOWAS has also prepared a 3,000-strong force that could be used to sideline the junta and put down the northern rebellion, but it remains unclear how the mission would be funded and what its mandate would be.

"It is time for the international community to do something instead of just making statements of compassion," said Mohammed Ag Touaf, a Timbuktu resident who worked as a customs officer before the crisis.

A school director outside of Timbuktu said that since Ansar Dine took control of the area, the curriculum was now controlled by the group, with male and female students separated and females forced to wear veils. A student, who declined to be named fearing for his safety, said classes now focused on Koranic teachings, instead of reading, writing and maths.

"Years of effort have been wasted," the student said. "The literacy rate will do nothing but go backwards."

A spokesman for Ansar Dine, Sanda Ould Boumama, told Reuters the group is working urgently to solve power and water shortages in Timbuktu, and to ensure that farmers in the area have what they need to cultivate crops.

But he said spreading Islamic teachings was the group's main objective. "We are in Timbuktu, an Islamic land. For us, there are no borders. The earth belongs to Allah."

(Writing by Richard Valdmanis; Editing by Robin Pomeroy)