Four soldiers were killed and eight others seriously injured by a roadside bomb in southeastern Niger, a region hit by jihadist attacks, the government said.

The troops were pursuing "terrorists" on Monday following an attack the previous day on a military position in Chetima Wangou in the Diffa region, the defence ministry said in a statement.

The world's poorest country, according to the UN Human Development Index, Niger is battling jihadists in the southeast on its border with Nigeria, and in the southwest, on its frontier with Mali.

Hundreds of lives have been lost and nearly half a million people have fled their homes.

On January 2, 105 people in two villages in the western region of Tillaberi were killed by jihadists who arrived on motorbikes.

It was the highest civilian toll in the Sahel since since jihadists launched a revolt in northern Mali in 2012 before advancing into Niger and Burkina Faso.

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