Nigerian security forces are investigating a possible mass kidnapping of villagers in the northeast state of Borno where Boko Haram Islamist militants abducted more than 200 schoolgirls two months ago, a security source said yesterday.

If confirmed, the latest abduction would fuel public frustration over Abuja's inability to quell Boko Haram's five-year campaign to carve out an Islamist state in the mainly Muslim north.

Military officials are looking into reports that suspected Islamist insurgents over the weekend raided at least three villages 60 miles from the state capital Maiduguri, the source added.

Two residents of the nearby village of Lassa, which wasn't attacked, told Reuters they spoke to people who reportedly fled as militants killed men and kidnapped "many" women and children.

Nigerian media reported that as many as 91 villagers had been abducted, most of them women and young girls. Reuters was unable to verify these accounts independently.