The Burkina Faso military has said it lost 11 soldiers during an attack on its base in Madjoari in the east on the country on Thursday.
At least 20 others were wounded by shrapnel or projectiles and received medical treatment, a statement by the armed forces' communications unit said.
No group has admitted responsibility for carrying out the attack yet.
Burkina Faso's army said its military air support killed at least 15 militants who were attempting to escape after the attack.
It urged all the units to maintain a spirit of combat readiness to defeat the enemy.
Col Paul-Henri Damiba, who overthrew President Roch Kaboré in the 24 January coup, has pledged to prioritise the security crisis by recruiting more forces.
He has also sought to establish local committees to initiate dialogue with militants.
Burkina Faso has been battling an Islamist insurgency in the north since 2015.