Intrigued, Amadou picked up a discarded grenade to play with outside an earth hut in central Mali. When he threw it, it exploded and he lost all the fingers on his left hand.
He is yet another victim of the explosive weapons left over from the months-long conflict between Islamist militants who occupied the country's north and the Malian authorities and their allies trying to push them back.
Since April last year 60 people have been killed or injured in this way. Children are often the first in line -- five dead and 38 hurt in the space of a few months, according to the UN children's fund UNICEF.
"The situation is extremely worrying," says UNICEF spokesman Laurent Duvilliers from the capital Bamako.
"200,000 children are at risk of injury or death in the north and centre of Mali because of these munitions that they want to play with."
Back in Mopti -- a city that lies on the edge of the country's north, where French-led troops have been battling jihadists since an offensive to reconquer the north began in January -- Amadou is being treated in hospital.
A white bandage covers the stump on his left arm. Dejected, the 19-year-old explains he took the grenade to have a look at what it was.
"I was curious, I unscrewed it to throw it and it exploded," he says softly under the white neon light of the hospital room.
"I'm angry at myself because I knew that it wasn't a good thing. But I'm also mad at those who brought this device into the city."
The explosion on February 28 etched a permanent mark on Amadou's family. His three-year-old brother has scars on his neck, chest and knee. The force of the blast also made a hole in a metal basin in front of their thatched-roof hut.
-- "An extremely worrying situation" --
Mopti itself was not the scene of fighting pitting jihadists against French-led troops.
But injured people still flocked to its hospital when clashes erupted in Konna, just 70 kilometres further north.
And according to Boubacar Diallo, director of the hospital, "jihadists have infiltrated the population."
"Over just a few days, we had two explosions. These are the collateral effects of war," he says, passing his hand over Amadou's head.
In Konna, Diallo adds, the situation is even worse. "There is ammunition scattered on the ground, grenades, and reports of shells that haven't exploded," he explains.
At the entrance of the city, "vehicles full of munitions that belonged to jihadists have exploded. But not everything has exploded so it creates a kind of dangerous field."
The two parts of the country most affected by abandoned weapons and ammunition are the north (Timbuktu, Kidal, Gao) and the centre (Konna, Diabali) where direct combat took place.
In a bid to limit this form of collateral damage, UNICEF and its partners have launched an awareness campaign.
People hand out comic strips in cities to try and make children more aware of the dangers and schools put informative pamphlets on display.
Already used in Afghanistan, the drawings have been adapted for Mali and have reached some 27,000 children so far.