Cameroon’s security forces repelled an attack early Wednesday in the northern town of Fotokol by gunmen suspected to be Boko Haram militants, Communications Minister Issa Tchiroma Bakary said.

The assailants targeted mosques and churches in the dawn attack, leaving at least 13 people dead, Bukar Mohammed, a resident who witnessed the assault, said by phone from Fotokol.

“They were repelled and some of them were killed,” Bakary said by phone from Yaounde, the capital. He said details of casualties weren’t immediately available and would be provided later.

Boko Haram has escalated its violent campaign to impose Shariah, or Islamic law, in Nigeria, Africa’s biggest economy and biggest oil-producing nation ahead of elections starting on Feb. 14. It has also increased attacks in neighboring Cameroon.

The Islamist group, which has declared a caliphate the size of Belgium in Nigeria’s northeast, killed more than 4,700 people last year, double the number in 2013, risk consultancy Verisk Maplecroft estimates.

Chad’s military captured the northeast Nigerian border town of Gamboru from Boko Haram on Feb. 3, the latest in a series of excursions into Nigerian territory as it battles the Islamist insurgent group.

African leaders agreed to set up a task force of 7,500 soldiers from Nigeria, Cameroon, Niger, Chad and Benin to counter Boko Haram, Ghana’s President John Dramani Mahama said Jan. 31 at a briefing in Accra, the capital of Ghana. The force will have its headquarters in N’Djamena, Chad’s capital, and a 12-month mandate starting in February, he said.