At least 29 Nigerien soldiers were killed in an attack by armed insurgents near the country's border with Mali, the Niger Defense Ministry said in a statement late Monday.

"The provisional toll of the attack is as follows, 29 soldiers fell in battle and two were wounded," the statement read.

Several dozen assailants were also killed, the statement said, but there was no further information on who was responsible for the attack.

Soldiers were returning from operations against militants when they were targeted by more than 100 assailants in vehicles using explosive devices, the defense ministry said.

The attack is one of the deadliest in the country since soldiers toppled the democratically elected leader of the country, Mohamed Bazoum, in a coup in July.

Three days of national mourning have been declared, the statement said.

Niger's relations with Western partners 

Relations between the West African nation and Western partners changed dramatically following the coup.

Niger, a French colony until 1960, was seen as the West's last reliable partner in battling jihadists in Africa's Sahel region.

Niger's security situation appeared to have been not as bad as that of neighboring Burkina Faso or Mali, which have also been battling an Islamist insurgency linked to al-Qaida and the so-called "Islamic State" group.

Last year, Niger was the only one of the three to see a decline in violence, according to the Armed Conflict Location & Event Data Project.

The French ambassador to Niger left the country last month after daily calls for the diplomat to exit since the coup. Germany and the EU have suspended aid to Niger.

rm/kb (Reuters, AFP)