Niger's parliament has unanimously approved sending troops to northern Nigeria as part of a regional offensive against the Islamist militant group Boko Haram that has launched several cross-border attacks in recent days.
Security sources said soldiers in Diffa, a town on Niger's border with Nigeria, shot dead a suicide bomber heading on foot towards a military base and warned that militants had infiltrated groups of civilians who had crossed into Niger.
Nigeria, Niger, Cameroon, Chad and Benin agreed at the weekend to send a joint force of 8,700 troops to battle the militant group, which has killed thousands of people and kidnapped hundreds more in its bid to carve out a caliphate.
Nigeria postponed its February 14 presidential election by six weeks, citing security concerns.
In the last few days, Niger has massed more than 3,000 troops in Diffa on its southeastern border with Nigeria, awaiting approval to go on the offensive.
"The pooling of the efforts and resources of concerned countries will contribute without doubt to crushing this group which shows scorn, through its barbaric acts, for the Muslim religion," Niger's parliamentary speaker Adamou Salifou said after the vote late yesterday.
The vote was supported by all 102 deputies present.
Yesterday, Boko Haram militants bombed Diffa, killing five people - its third attack there in four days. It also carried out raids in neighbouring Cameroon, kidnapping a bus full of passengers.
Locals in Diffa, which lies just a few miles from territory controlled by Boko Haram, have long spoken of sleeper cells infiltrating their communities.
Several security sources warned that militants, who had been living among civilians in northern Nigeria, were among those who had fled into Niger with them.
"Most of the Boko Haram fighters who have operated in Diffa have come from these displaced. They are Nigerian refugees or people from Niger who had been in Nigeria," one officer said.
"There are real networks," he said.
An intensification of Boko Haram violence near Lake Chad, which straddles Nigeria, Chad, Cameroon and Niger, has sent tens of thousands of Nigerians fleeing across the border.
Diffa was mainly quiet on Tuesday but residents were scrambling for buses out.
"The situation in Diffa is very serious," Niger Defence Minister Karidio Mahamadou said on a private radio station.
"We will do everything to protect the population. We will wage war against Boko Haram all the way to its last hideout."
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