Security sources informed AFP on Sunday that suspected terrorists ambushed and murdered 13 soldiers in Burkina Faso's eastern province, the most recent act of violence to rock the country, which has been rocked by insurgency.

According to one of the sources, the attack on Saturday along the road connecting Fada N'Gourma and Natiaboani also injured four members of the defense forces.

"Reinforcements have been deployed to secure the zone and carry out a search," a second source added, confirming the casualty toll. The unit that came under fire had been sent to relieve a detachment from Natiaboani.

Read next: 10 Burkinabe soldiers killed in attack on military base

A military installation in Djibo, a significant northern town that has been under a jihadist blockade for three months, was reportedly attacked on Friday, according to the influential Support Group for Islam and Muslims (GSIM), which is affiliated with Al-Qaeda.

The military reported that during the terrorist attack on the 14th regiment on Monday, at least 10 troops were killed and 50 were injured. The army added it killed 18 terrorists in mopping-up operations.

The attack on a supply convoy bound for Djibo on September 26 that resulted in 37 deaths, 27 of which were troops, was also blamed on GSIM. Several dozen truck drivers remain missing. That assault helped trigger the latest coup in Burkina just four days later, led by young army captain Ibrahim Traore.

He became interim President on October 21, vowing to win back territory from terrorists. 

Read next: 3 soldiers, 8 civilian auxiliaries killed in ambush: Burkina Faso

It was Burkina's second coup in eight months, motivated by a seven-year insurgency that has displaced almost two million people and taken thousands of lives. The new government on Wednesday declared securing the Sahel state's territory would be a top priority.

More than a third of the national territory remains outside government control.

As the number of attacks rises, the authorities also started a campaign to enlist 50,000 civilian defense volunteers to support the army. 4.9 million people, or a fifth of Burkina's population, are in urgent need of aid, a UN representative warned last week, citing the fact that many "mothers were compelled to feed their children with leaves and salt."