The armies of Niger and Chad today launched a major ground and air offensive against Islamist extremist group Boko Haram in north-eastern Nigeria, a source from the Niger government said.

The offensive opened up a new front against the Islamists as part of regional efforts to combat them and came after Boko Haram leader Abubakar Shekau pledged allegiance to the Islamic State group in an audio message.

“An offensive is underway against Boko Haram,” the source told AFP. “Very early this morning, the troops from Niger and Chad began an offensive against Boko Haram... in the area of Bosso and near to Diffa.”

A resident of Diffa, located in Niger near the Nigerian border, told AFP he saw troops headed toward the frontier early Sunday followed by the sounds of heavy arms fire.

“After some time, the detonations grew further away, an apparent sign that the troops were moving inside Nigeria,” he said.

Privately owned radio station Anfani, based in Diffa, reported more than 200 vehicles, including those equipped with machine guns as well as tanks, ambulances, water tankers and transport trucks, in a convoy moving toward the Nigerian border.

It also reported that aircraft had targeted Boko Haram positions on Saturday and early Sunday.

An aid worker told AFP heavy arms fire was coming from the direction of the Doutchi bridge connecting Niger to Nigeria on Sunday morning.

On Friday, the African Union endorsed the creation of a regional force of up to 10,000 men to join the fight against Boko Haram.

The force, the idea for which was adopted at an AU summit in January, will be based in Chad’s capital N’Djamena, the pan-African bloc’s Peace and Security Council said.

It will be mandated “to prevent the spread of Boko Haram activities and other terrorist groups” and “eradicate their presence,” the body agreed in a meeting earlier week.

Diplomats said Chad, Nigeria, Cameroon, Niger and Benin had committed to providing troops, who would “operate freely” in a still-undefined region.

Regional efforts have however already been underway to fight Boko Haram for several weeks, particularly in the Gamboru area of Nigeria on the border with Cameroon. The borders of Nigeria, Chad, Niger and Cameroon converge in the region around Lake Chad.

The Islamists have apparently been pummelled out of captured territory by the Nigerian army and its regional allies and have returned to their previous campaign of urban guerrilla warfare.

With Boko Haram squeezed out of captured territory, security analysts have predicted a rise in bomb attacks in towns and cities, including to disrupt elections in three weeks’ time.

Nigeria postponed its elections initially scheduled for February to March 28 after security chiefs said they needed more time to weaken Boko Haram.

Shekau has vowed to disrupt the vote and widespread attacks, especially near polling stations, could prove disastrous.

•Text courtesy of AFP. Photo shows Chadian troops on patrol.

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