A source in the town of Kaya north of the capital said demonstrators tried to approach French army personnel on a strip of wasteland where they had spent the night.

"As the protesters tried to get closer, soldiers fired warning shots", and some received "gunshot wounds", they said.

A medical source said "the emergency department at the Kaya hospital received four people with gunshot wounds".

The Sidwaya daily paper said three were wounded, one shot in the cheek.

It was not immediately clear which side had hit the protesters.

A French military source denied anybody had been wounded, rejecting any responsibility.

"A group of protesters tried to cut through the fence to enter the area and the Burkinabe soldiers fired tear gas to disperse the crowd," they said.

"The French soldiers fired a few warning shots over the crowd. Nobody was wounded because of the actions of the French military personnel.

"We do not know of any person who was wounded, even after tear gas was fired."

The convoy is crossing through the former French colony on its way from Ivory Coast to Niger.

It had already been held up this week by protests in the western city of Bobo Dioulasso and in the capital Ouagadougou, where local security forces had to fire tear gas to disperse the demonstrators.

French troops are in the wider region as part of efforts to fight jihadists there.

The French army source said the convoy of some 60 trucks was "not carrying weapons to the jihadists as can be read on social media".