MAIDUGURI, Nigeria (AP) — A Nigerian security official says the Boko Haram (BOH’-koh hah-RAHM’) militant group kidnapped 100 people last weekend, but most were freed by security forces from neighboring Chad.

A member of an anti-Boko Haram vigilante movement says 20 females and about 70 young men were forced to board speed boats in Lake Chad, which lies on the border between Nigeria, Niger, Cameroon and Chad.

The official says Chadian security forces intercepted the group as they crossed the Chad border, killing many of the fighters and setting free most of the captives. He spoke on condition of anonymity because he was not authorized to speak to the media.

In mid-April, Boko Haram kidnapped more than 200 schoolgirls. They have still not been freed.

Boko Haram has intensified its violent campaign this year to enforce an Islamic state in Nigeria, whose population is almost evenly divided between a mainly Muslim north and largely Christian south. Amnesty International says more than 4,000 people have been killed by all sides in the conflict, including Nigerian security forces.

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