Boko Haram fighters launched an attack on a prison in Diffa overnight, with the gun battle continuing until government forces drove the rebels back on Monday morning. The extremist group followed up the failed attack with a bomb blast at a local market some hours later.

"Everything blew up - I saw bodies everywhere," a local merchant told the AFP news agency Monday.

No death toll was immediately available.

Authorities ordered locals to stay indoors and set up roadblocks around Diffa by Monday morning. Thousands of people were fleeing from the town in cars and motorbikes, according to residents and humanitarian officials.

A journalist in Diffa said he saw the bodies of alleged Boko Haram fighters being moved but was unable to count them, and that some of the rebels attempted to hide within the town. The city has been attacked multiple times since Friday.

"The soldiers are looking for them, weapons at the ready. The army has encircled Diffa," the journalist said.

Against 'forces of evil'

This latest series of attacks comes as Niger's parliament has decided to join the regional offensive against the terrorist group.

The governments of Cameroon, Niger, Nigeria and Benin have agreed to create a multinational force of 8,700 soldiers to fight the Islamists. The Boko Haram movement, based in northeast Nigeria, has promised to attack the countries aiding Nigeria in its fight against the rebels.

On Sunday, the group also captured a passenger bus full of people in neighboring Cameroon, with AFP reporting that 12 men had been executed. The surviving eight women have since been released, according to a resident whose wife was among the kidnapped.

"We will defeat Boko Haram. Boko Haram has no future in this region," Niger President Mahamadou Issoufou told reporters on Monday in the capital, Niamey.

Niger's Defense Minister Mahamadou Karidjo said his troops were ready 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.

'God's soldiers are victorious'

Boko Haram leader Abubakar Shekau mocked the anti-terrorist coalition in a video posted Monday.

"You are sending 7,000 of your soldiers. Why don't you send 7 million? The 7,000 is little and we can kill them step by step ... Your soldiers are infidels and God's soldiers are victorious," he said.

Shekau also urged the people of Chad and Cameroon to reject democracy to be true Muslims.

"This message is for the people and leaders of Africa. You cannot defeat us ... Sit back and rethink. Is your constitution and democracy better than Islam?" he said.

dj/cmk (Reuters, AP, AFP)