NIAMEY (Reuters) - Unidentified armed men have killed 37 civilians in the commune of Banibangou in southwest Niger, according to internal security service memos shared by a security source and a former official on Tuesday.

       The attack occurred on Monday in an area near the Malian border where Islamist militants have repeatedly massacred civilians this year.

       (Reporting by Moussa Aksar and Boureima Balima; Writing by Alessandra Prentice; editing by Edward McAllister)