A cultural treasure of sub-Saharan Islam, hundreds of thousands of priceless parchments sit on metal shelves in Mali's capital as archivists painstakingly classify and digitise them.

They have endured the ravages of time and militant fury, but the Timbuktu manuscripts may yet perish, far from their fabled home in the shifting sands of the northern Mali desert.

Their clandestine passage to Bamako will remain one of the most remarkable episodes of the silent resistance to jihadism in northern Mali, documented to widespread acclaim in the Oscar-nominated movie "Timbuktu".

The vast majority were spirited away as Islamists torched part of Timbuktu's Ahmed Baba Islamic Research Institute in January 2013 as they fled a French-led offensive on their northern bastion.

The insurgent fighters had already destroyed many of the city's centuries-old shrines, the iconic legacy of Timbuktu's golden age of intellectual and spiritual development.

The fighters took the city in April 2012, swiftly implementing a version of Islamic law which forced women to wear veils and set whipping and stoning as punishment for transgressions.

Islamist fighters had considered the texts and the shrines -- which helped earn the city UNESCO world heritage status -- to be idolatrous.

"It was me who brought the manuscripts here," says Mohammed al-Kadi Maiga, of the Ahmed Baba Institute, which is ensuring their preservation in Bamako.

The librarian organised the clandestine smuggling in three stages of thousands of tracts on astronomy, physics, chemistry and literature, hidden in trunks, backpacks and bags of rice.

"We saw how in Iraq manuscripts and cultural artifacts were ransacked," he said, explaining how the 2003 US invasion led staff and families housing private collections to conclude that their own heritage must be rescued.

"If they had stopped us, maybe they would have cut off our hands," Maiga shuddered, proud to converse with colleagues in classical Arabic, a language imposed by Timbuktu's brutal new masters to enforce their authority.

Perilous return

Lazarus Eloundou, the head of UNESCO in Mali, estimates that at least 370,000 manuscripts were smuggled out of Timbuktu and the surrounding area.

But he laments the "incalculable loss" of around 4,200 which went missing - burned or otherwise destroyed.

"Those who destroy, they do so to impose on communities in the territories they occupy their own conception of life, culture, religion, the better to dominate these populations," Eloundou said.

"When they want to erase your history, they want to show that you have never existed before."

The collection's wealth of knowledge, still largely unexplored, contains manuscripts dating back 800 years.

The tomes, mostly in Arabic and Fula -- a language widely spoken across west Africa -- covered a variety of subjects: astronomy, botany, music, law, history and politics.

In the Ahmed Baba Institute's makeshift building in Bamako, a 12th-century biography of the Prophet Mohammed shares shelf space with a Hausa-language Koran from the 18th century.

A copy of the 1880 Treaty of Madrid, guaranteeing consular protections in Morocco to Western nations, is preserved nearby.

If these artifacts are to survive they must make their way back to Timbuktu, a return as potentially perilous as the outward journey, experts warn.

"It is essential to preserve these ancient manuscripts, currently in Bamako, against the risk of rapid deterioration to which they are exposed," concluded participants in an international conference on this subject in the Malian capital late January, calling for an "emergency plan".

"Returning the manuscripts to Timbuktu is an obligation, a duty. We have no choice but to send them back one day to Timbuktu. But when? That is the question," Abdul Kadri Idrissa Maiga, the director of the Ahmed Baba Institute.

"First, we must first restore the premises so that they are suitable to receive these manuscripts. You also need maximum security," he said, pointing to the unstable situation in the north.