The Islamists hijacking a rebellion in Timbuktu
Some residents have been abandoning the city of Timbuktu in Mali because of the deadly unrest hitting the West African nation, but others have stayed there despite the tension.
I was alone, and ambling through the cheerfully shambolic market in Timbuktu, swerving to avoid the donkeys, and stopping to chat to some of the traders.
For the past week everyone, from the governor to my guide and translator, Halis, had been earnestly assuring me that Timbuktu was safe. The threats of al-Qaeda, and of kidnapping, were being wildly exaggerated.
I got talking to an Arab trader in the market. Friendly enough. But when he asked me what hotel I was staying at, a small mental alarm bell rang, and I changed the subject.
A few minutes later, I found my guide Halis, and mentioned the conversation to him. His smile was chased away by something close to panic.
I know I said it is safe here, he said. But you need to be careful.
That was 2009.
Today - the worst, half-formed fears of many in Timbuktu have turned into a choking reality.
The headlines tell a story of sudden, unexpected catastrophe.
First, came the revolution in Libya. When it ended, weapons flooded south across the Sahara.
That prompted some Tuareg tribesmen - dreaming of an independent state in northern Mali - to launch an armed rebellion earlier this year.
But the rebellion was hijacked.
Islamist militants, many from neighbouring countries, charged across the sand dunes - with even more guns and more money.
And today, Timbuktu is under Sharia law.
Gunmen patrol the streets, arresting men for smoking, forcing women to veil their faces.
The town's ancient Islamic shrines - the mausoleums of local Sufi saints - are being methodically torn down, and ploughed back into the Saharan sands, by militant outsiders who believe, scrupulously, that intolerance is a virtue.
Of course the roots of all this go back far beyond the last few months.
The modern world has not been kind to the tribes scraping a living from the barren fringes of the desert.
Climate change is part of it - but ships and planes and globalisation have also destroyed the need for the camel trains that used to bring legitimate goods across the Sahara.
So the smugglers took over - ferrying drugs, guns, and migrants towards Europe.
Then came the militants, hiding in the desert among the smugglers, making money from kidnapping - destroying Mali's emerging tourism industry in the process.
Now, Timbuktu is half empty. Halis has fled, so has anyone else with the money and the opportunity.
I have been speaking by phone to several people who have stayed on. All of them asked me not to use their names.
"I am very scared," said one man who used to work in the tourism industry. "My family cannot leave the house any more. We thought these people were rebels. But they are not.
"They are al-Qaeda. They steal everything. They are not good Muslims. We eat once a day. Sometimes not at all. And now they go to our mosques and destroy all our important things. Some are 400 years old."
I have never been to a place more in touch, more enthralled, with its own history than Timbuktu. It may be a dusty backwater these days, but it was once the Oxford of Africa - a thriving 15th Century university town. People still keep boxes of ancient manuscripts in their storerooms, and garages.
The former South African President, Thabo Mbeki, helped to organise the building of a new library and research centre to save the manuscripts for future generations.
Timbuktu, he said, was a critical link to Africa's glorious past - a place that refutes the ignorant, racist, "Tarzan and savages" view of the continent's history.
When I was there in 2009, the new library had yet to open, but workmen supervised by international experts, were stripping back layers of ancient mud from the giant Sankore mosque in the centre of town, then carefully slapping on a new, glistening coat.
This week, the town's new guardians have been hard at work, attacking shrines with pickaxes and shovels, and destroying the door of another important mosque - a door that, according to local tradition, will bring misfortune if it is opened.
There is talk now of a military offensive, led by Malian government troops and neighbouring armies, to liberate a region that many fear is becoming a new hub for militants from Nigeria to Somalia and beyond.
In theory, it should not be too hard. On a map, the region looks vast - the size of France. But it is mostly desert, with a handful of small towns, now largely abandoned by the civilian population.
Still, these things take time. Who knows what will be left of Timbuktu's heritage?
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