Some victims were shot, while others had their throats cut. Police have given few details, but say it appears it was a targeted attack. Witnesses report hearing the gunmen shouting out names of their victims during the assault.
No one has claimed responsibility and no arrests have been made so far.
Meanwhile in southern Nigeria, 12 policemen are missing after militants ambushed their boat stalled in a creek. It is unclear who was behind the attack. It came two days after the MEND militant group threatened to resume attacks following the jailing of one of its leaders in South Africa.
