The attack carried out by hundreds of Boko Haram fighters in the village of Baroua in southeast Niger wounded nine others, Nigeria's Defence Ministry says.
An attack by hundreds of Boko Haram fighters on a town in southeast Niger killed 16 soldiers and wounded nine others, the Defence Ministry said.
The attack took place in the village of Baroua, in the Diffa region bordering Nigeria, where Boko Haram is active along with the ISIS West Africa Province (ISWAP), a branch of the Daesh terror group.
In the assault late on Tuesday "the positions of our defence and security forces ... were attacked by several hundred Boko Haram elements who came from Lake Chad,” Defence Minister Alkassoum Indatou said in a statement.
Around 50 attackers were killed in the ensuing combat and "a large quantity of arms and ammunition" were recovered, he added.
The attack came only two months after around 6,000 people returned to the Baroua area in June after fleeing violence in 2015, under a programme to encourage around 26,000 inhabitants of the region to go back to their homes.
Authorities had said that 19 villages like Baroua were under "reinforced" protection - although Diffa governor Issa Lemine also hailed the "positive development of the security situation" as he welcomed returnees.
Those who fled had been living in safer villages, UN camps or with relatives elsewhere in the region.
The Diffa region hosts approximately 300,000 Nigerian refugees and internally displaced Nigerians, according to the UN.
Niger, the world's poorest country by the benchmark of the UN's Human Development Index (HDI), has been battling a Boko Haram insurgency since 2009, which has spilled into neighboring countries.
On August 16 at least 37 civilians including women and children were killed in an attack on a village by attackers who arrived on motorbikes.
Two weeks before, 15 soldiers were killed in an ambush.