YAOUNDE, Cameroon -- A military official says two female suicide bombers have staged attacks in north Cameroon, killing at least five people.

Col. Jacob Kodji said Saturday that one teenager set off explosives in a local shop, killing two people, and the other targeted a family in the town of Dabanga near Cameroon's northern border with Nigeria. He said the suicide bombers were Nigerians who came to Cameroon as refugees.

Kodji says 12 others were injured and are receiving treatment at a military camp in Mora.

No group claimed responsibility for the attacks which are in line with others launched by Nigeria's Boko Haram extremists.

This year Boko Haram has expanded attacks into Cameroon, Chad and Niger -- all countries contributing troops to a regional force intended to wipe out the extremists