Jihadist rebels last week blew up two bridges in northern Burkina Faso in a bid to isolate key towns in the region, the army said on Tuesday.
Highway bridges at Wousse and Nare were blown up almost simultaneously on Friday, the military said.
Residents in Dori and Djibo said their towns remained inaccessible by road on Tuesday.
The Nare bridge had recently been repaired after being damaged in a bomb blast on June 30.
The attacks are “an attempt to isolate” the towns, the military said.
One of the world’s poorest countries, Burkina Faso has been shaken by jihadist raids since 2015, with the movements linked to Al-Qaeda and the Islamic State group.
Thousands of people have been killed and around 1.9 million displaced.
The government only controls around 60 percent of the country, West Africa’s mediator for the country said last month.
Burkina Faso’s ruling junta last month announced it would create two “zones of military interest” in the north and east of the country that are reputed havens for jihadists.
In these areas, “human presence is forbidden” — a move aimed at giving the army freer range to crack down on the rebels.
Blowing up the bridges “could aim at preventing people from leaving the military zones and enable the terrorists to remain mingled with the population,” thus hampering the operation, said Mahamoudou Sawadogo, a security expert.
Other attacks in the north this year have “systematically” targeted telecommunications and strategic installations, including an airfield at Ouahigouya, he said.