Islamic State-affiliated militants have stepped up attacks in western Niger, killing more than 127 people in five separate strikes since March and highlighting authorities' failure to protect civilians, Human Rights Watch (HRW) said on Wednesday.

A report by the rights group provides the most detailed accounts available of attacks carried out by Islamic State in the Sahel Province (ISSP) in the Tillaberi region, near the border with Burkina Faso and Mali. Niger does not typically comment on such incidents.

The tri-border region is known as a hub of jihadist activity in West Africa linked to Islamic State and al-Qaeda.

Witnesses identified the perpetrators of the attacks as members of ISSP based on their attire and because of threats the group had made beforehand, HRW said.

Witnesses also said Niger's army did not adequately respond to warnings of attacks and ignored villagers' requests for protection, according to the report.

The government and a military spokesperson could not be reached for comment ahead of the report's publication.

Reuters could not independently verify HRW's accounts of the attacks.

Niger's junta, which came to power in a coup in 2023, cited persistent insecurity as justification for overthrowing the government.

But an analysis of data on attacks and casualties in the country had shown an improvement in security ahead of the coup, owing to government tactics and help from French and US forces.

The resurgence in attacks in Tillaberi underscores the threat posed by jihadist groups at a time when West African governments are estranged from former Western military allies

HRW urged Niger's government to investigate and prosecute abuses it described as apparent war crimes. The group said Niger's justice minister did not respond to questions about its findings.