More than 50 members of Niger's security forces have been killed in two separate attacks in the west of the country, according to security sources.
According to Report, citing Reuters, a convoy of gendarmes was ambushed near the town of Abala-Filingué last Wednesday, while another attack in Birni-N'Konni on Saturday killed more than 30 soldiers.
The sources described the assailants as terrorists but provided no further details.
The Islamic State Sahel Province, the West African affiliate of Islamic State, claimed responsibility for both attacks in statements issued on Sunday, according to the SITE Intelligence Group.
The group also carried out an attack on the civilian airport and military airbase in Niger's capital, Niamey, in January.
Analysts and security sources say frustration has been growing among frontline army units following repeated losses to insurgent groups, particularly in western Niger.