Ibrahim Ould Hannoush clings to his staff, trembling and stammering as he is interrogated in his native Tamashek language by Malian soldiers who believe he may have links with Islamist militants.
The suspect is bombarded with questions from the men, who are hunting insurgents in a valley in northern Mali as part of Operation Gustav, one of France's largest military operations during its three-month intervention in its former colony.
Hannoush insists he is a simple Tuareg shepherd living with family in the arid Inais valley, which the French believe to be an important logistics base for the Al-Qaeda-linked "Movement for Oneness and Jihad in West Africa" (MUJAO).
But the Malian security forces helping the French seek out the militants aren't buying his story.
"Does he know something about the terrorists?" a policeman demands.
A Tuareg special forces soldier translates: "He said he saw three on a motorbike yesterday but that even the French had seen them."
Off to the side, Chief Warrant Officer Alo Mazzak Agnamaka, also from the Malian special forces, glowers at Hannoush.
"He may not have taken up arms but he's still complicit. It's not possible to know nothing in this valley," he says.
"Where does he think they've gone?"
"That way," Hannoush replies, pointing eastwards. "Three days ago, in five vehicles, they came through here."
The warrant officer, frustrated with the quality of information Hannoush is offering, mumbles into his scarf.
"He won't tell us anything. It's not worth bothering, no one can talk. They are all in the same situation."
A thousand French troops backed by tanks and covered from the air went into the Inais valley, a dry river basin 160 kilometres (100 miles) north of Gao, Mali's largest northern city, at the launch of Operation Gustav at dawn on Sunday.
The mission comes as France prepares to withdraw three-quarters of the 4,000 troops it deployed in January to block a feared advance on the Malian capital Bamako by Al Qaeda-linked insurgents.
France's intervention has driven the militants from most of their northern strongholds but Paris is preparing to hand over to a UN-mandated African force in the coming weeks, leaving just 1,000 of its troops to fight terrorism.
The extremists had occupied Mali's northern settlements, including the fabled Saharan caravan town of Timbuktu, terrorising locals with amputations and executions performed under their brutal interpretation of sharia Islamic law.
While French-led troops have inflicted severe losses on the Islamists, soldiers are still battling significant pockets of resistance around Gao, where MUJAO are the most active rebel group.
French and Malian troops have discovered numerous caches of ammunition, often very high calibre, in the Inais valley but very few weapons.
They are relying on information from the local population of semi-nomadic Tuareg pastoralists to help them seek out and destroy as much of MUJAO's logistic infrastructure as possible, but they are under no illusions.
In a sparsely populated region where everyone watches and no movement goes unnoticed, it can be fatal to be seen talking to "infidels".
"I'm taking a risk talking to you in broad daylight," a young man who asked to be identified only by his first name, Mohammed, told AFP.
"The French are here and that's fine, but soon they will leave. MUJAO will return, and they are very bad people.
"When they were in the woods at the bottom of the river basin, they arrested everyone they saw passing near their camps.
"One day, they tied my little brother to a tree for a whole day with nothing to drink, to make him confess that he had turned into a spy."
Intimidated by the questioning and threats, Ibrahim Ould Hannoush finally admits in a barely audible voice that he perhaps knows the location of a cache of petrol.
He is put into a French armoured vehicle and taken in a convoy to an arid area of the valley, but once he gets there he is no longer sure, telling the soldiers he remembers trees, and then stones. Then he claims to have "just forgotten".
"A young man told us yesterday that when they came to get supplies, the men from MUJAO beat people," says a French officer who will only identify himself as Captain Cyril.
"You have to understand, these people are terrified."
Another villager, who asks to remain anonymous, says that "jihadists often spent the night in columns of four or five Toyotas, headlights off. They fill their flasks at the well, sometimes buy oil, sugar and tea."
"Buy, you say. In this valley, they own everything," the Tuareg officer says, returning to his pick-up.
"Without the French, in two weeks we will not be able to get within two miles of this area. They will be more numerous and better armed than us again."