Farms are abandoned, banks and schools have closed across towns in northern Cameroon following violent cross-border attacks by the Islamist militant group Boko Haram this month.

Life in the north “has been disorganized, distorted,” Cameroon’s Communications Minister, Issa Tchiroma Bakary, said by phone from the capital, Yaounde, on Thursday. “Farmers can’t go to farm, children can’t go to school.

Our businessmen are finding it difficult to cross to Chad and Nigeria due to the possibility of attacks,” he said.

Cameroon’s remote north has been the scene of increased fighting between the military and members of Boko Haram, who have stepped up their campaign of violence ahead of Nigeria’s presidential elections in February. Cameroon and Nigeria share a 1,690-kilometer (1,050-mile) border that stretches from the Atlantic Ocean to Lake Chad in the north.

It’s unknown how many people have fled the border area. Some residents have traveled to Yaounde, while others fled to neighboring Chad and Niger, according to Sulaiman Abdullahi, a resident of the border town of Amchide. “We have a large family in the region,” Abdullahi said by phone from Yaounde.

“All of us fled the town. I knew a lot of people that were slaughtered like a ram.”

The Islamist militant group released a video threatening to attack more countries after the African Union said it backed plans by a number of states in the region to form a joint force to fight Boko Haram. Cameroon, Chad, Niger, Nigeria and Ghana are prepared to provide troops to a regional force, according to Ghanaian President John Dramani Mahama in an interview last week.

Chad has sent elite troops and equipment to assist Cameroon.

Niger hosts more than 100,000 displaced, including 25,000 children, in the eastern city of Diffa. Among the refugees from Cameroon is Bukar Fannami, who said he spent two weeks hiding under a bed after insurgents took over the border town of Damasak.

“I survived on raw millet given to me by an old woman, I was lucky to sneak out of Damasak,” he said by phone.

Boko Haram has killed more than 13,000 people in Nigeria since 2009, according to the government. The group has claimed responsibility for gun attacks, bombings and kidnappings.