YAOUNDE, Cameroon — A suicide attack by suspected members of Nigerian Islamist militants group Boko Haram killed at least 10 people over the border in the Far North region of Cameroon on Saturday, security sources said.

Boko Haram has mounted numerous attacks in Cameroon, Chad, Niger and Nigeria this year and is turning the border region near Lake Chad into a war zone, the United Nations refugee agency said last month.

"The initial figures speak of 10 dead including the suicide bombers and around a dozen wounded," said a senior Cameroonian army commander of the attack on the village of Nigue, a suburb of Fotokol town.

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Boko Haram has waged a six-year campaign for an Islamist state in northeastern Nigeria. Neighboring countries joined an offensive against the group this year and the conflict spilled across their borders, displacing tens of thousands of people.

Boko Haram used Cameroon's impoverished Far North to stockpile supplies and recruits until the government cracked down last year.

Cameroon is also in an 8,700-strong regional force led by Nigeria against the militants, expected to be operational by the end of the year. The United States is sending military supplies and troops to the central African country to aid the fight.