Nigeria's Boko Haram fighters launched a new attack in neighbouring Niger, as parliament in Niamey was set to vote on joining a regional force against the Islamists.
The insurgents raided a prison in the southeastern border town of Diffa, which they first attacked on Friday, but were repelled after a heavy exchange of fire, humanitarian sources said.
"The attack failed. The assailants were quite easily pushed back," one source told AFP.
Niger's parliament was expected on Monday to support a proposal to deploy troops inside Nigeria to help in the battle, along with soldiers from Chad, which has a battle-hardened army, and Cameroon.
No casualty toll was immediately available after the raid by Boko Haram, which has widened a deadly six-year insurgency in Nigeria with attacks in neighbouring countries.
A journalist in Diffa said he saw the bodies of Boko Haram fighters in a hearse but was unable to count them.
Some Boko Haram fighters sought to hide out in the town. "The soldiers are looking for them, weapons at the ready. The army has encircled Diffa," the journalist said.
Another journalist said some of the fighters were being held in the prison they attacked.
Boko Haram leader Abubakar Shekau vowed in a new video released on Monday to defeat the military force taking shape to fight the militants in Nigeria, Cameroon and Niger.
The small nation of Benin on Nigeria's western border on Saturday agreed to join the alliance, which would include 8,700 troops, police and civilians.
But Shekau dismissed the force, previously set at around 7,500, saying: "We can seize them one by one."
Niger's Defence Minister Mahamadou Karidjo said Sunday that he hoped for a favourable parliamentary vote to "bring the final blow against the forces of evil".
"The boys are chomping at the bit to go" to fight Boko Haram, he said on public television.
