A group of jihadis came knocking at the gate late on Wednesday night last week. But the Ahmed Baba centre in the Malian city of Timbuktu is not the kind of library that would accept visitors after dark.
The Islamist militants tricked the guard and said they were coming to secure the place. But once inside, they ransacked the centre's reading room.
When historian Abdoulaye Cisse arrived early in the morning, the pile of ashes was still warm.
"They probably spent most of the night in there," he said.
Dozens of empty handcrafted boxes still litter the floor of the hallway. Ashes haven't been removed yet either.
A few people come in and out surveying the irreparable damage and lament the remains of a cultural trove kept in Timbuktu for centuries.
At least 2,000 manuscripts were stored in this centre that was opened in 2009, funded by the South African government.
The project was meant to catalogue and preserve the city's historical documents, many of which continue to be held by families or smaller libraries.
Another 28,000 were due to be transferred to the Ahmed Baba premises but were instead sent to the capital after al-Qaeda militants arrived in the city last year.
Each box is tagged with a reference number and if the search is properly done, these tags should reveal the full extent of the damage.
It could also reveal how many were simply stolen.
"These fighters know too well how much these papers are valued, it's a huge wealth that will be impossible to replace," Mr Cisse told the BBC.
"When I surveyed the reading room, I found about 30 left so I brought them home to secure them," he said.
The offending texts ranged from history to geography and astronomy, medicine and Islamic law; writings dating back in some cases as far as the 13th Century.
In the reading room, shelves were emptied and the desk equipped with a magnifying glass vandalised.
Named after a saint of the ancient city who wrote many manuscripts himself, the Ahmed Baba centre stands out for its modernity but was designed to echo the famous Timbuktu style of dry-mud walls.
The Islamist militants prepared to flee last week knowing that an assault by the French-led forces on their positions here was imminent.
But in their haste, they took the time to commit one last act of vengeance.
They had sparked worldwide condemnation last year when they destroyed sacred tombs and shrines designated as Unesco World Heritage sites on the pretext that they violated principles of Islamic law.
Elhadj Djitteye, who used to guide visitors in town, reckons that the fighters linked to al-Qaeda carried out the attack on the library in response to the French military intervention ordered earlier in January by President Francois Hollande.
Noting that the jihadis hadn't touched the manuscripts in 10 months of occupation, Mr Djitteye sadly comments that they "hit Timbuktu straight at its heart".
The militants' destructive parting gesture left many residents feeling that another part of their celebrated city's history had just been erased.
The people of Timbuktu have been anxious to return to some kind of normal life since the French and Malian troops entered they city and were hailed as "liberators".
Reminders of the extremists, like the black banners proclaiming sharia at the city gates, are being removed.
But in just under a year, the Islamist militants have inflicted lasting damage on Mali's most renowned cultural centre. The scars left by Timbuktu's occupation are likely to take much longer to heal.