Islamic extremists from Nigeria attacked a town inside the neighboring country of Niger on Friday, marking the second foreign country attacked by Boko Haram this week. The attackers were later repelled by forces from Chad and Niger, witnesses said.

The incursion comes as Niger and several other African countries are planning to send troops to battle the Islamic extremists, seen as a growing threat not only to Nigeria but to the region of West and Central Africa. Chad and Cameroon in recent days already began using its military forces to attack Boko Haram.

It was not immediately clear if there were casualties in the early morning attack on Bosso, the Niger town bordering northeastern Nigeria. Soldiers from Niger and Chad rushed to the scene and engaged in an hour-long firefight in which Boko Haram retreated, leaving the streets deserted, said Abba Hassan, a pharmacist in Bosso.

“Niger and Chadian planes are conducting surveillance at the moment in town and troops on the ground are combing through the streets,” Hassan told The Associated Press by phone.

French radio station RFI also carried news of the attack, citing local residents.

Niger’s government spokesman and foreign affairs minister could not immediately be reached for comment. Niger’s president was meeting with his Cabinet.

The area of Niger where the attack took place is where refugees already have arrived by the thousands seeking safety from Boko Haram violence in Nigeria.

In a Jan. 31 message, Boko Haram fighters vowed to seek revenge on Niger if they aided the growing military effort by several African nations against the terror group.

“Their government is leading them into a dark tunnel if it joins a coalition with Chad and Cameroon against us, that it will use their sons in a war in which they have nothing to gain but fighting against Allah and His messenger,” said a transcript released by SITE intelligence monitoring service.

On Wednesday and Thursday, Boko Haram fighters attacked Fotokol, in Cameroon and about 100 kilometers (60 miles) from Bosso, leaving nearly 100 people dead and some 500 wounded, according to Cameroonian officials. The extremists razed mosques and churches and used civilians as human shields before Cameroonian forces pushed them back across the border to Nigeria.

“Cameroonian soldiers assisted by Chadian forces have successfully chased hundreds of Boko Haram fighters out of the Cameroonian locality of Fotokol on the border with Nigeria,” said Cameroon government spokesman Issa Tchiroma Bakary.

The cross-border assaults came after Boko Haram was bombed out of several Nigerian towns earlier this week by Nigerian and Chadian jets. Cameroon and Chad joined Nigeria in launching an air and ground offensive against the insurgents on at least two fronts this week.

More neighboring countries are mobilizing to help Nigeria fight Boko Haram. Regional leaders are meeting Friday for a second day in Cameroon’s capital, Yaounde, to finalize plans for a coordinated military response to the terror group blamed for killing 10,000 people over the past year.

Last week, leaders of the African Union authorized a 7,500-strong force to fight Boko Haram, including pledges of troops from Nigeria and four neighboring countries, Cameroon, Chad, Niger and Benin. The United Nations have offered logistical support. The deployment of the multinational African force could be could be delayed by funding issues.

AP