The vigilante, Bukar Kyari, told CNN the captives escaped the camp while the militants were in nearby Damboa launching an attack. "The women seized that rare opportunity to escape when they realized they were alone in the camp."
The women, in addition to five others who are not yet accounted for, were kidnapped by Boko Haram from the Kummabza village in northern Borno state on June 18.
Boko Haram made international headlines in April when the group abducted more than 200 girls from their boarding school in northern Nigeria. The group is still believed to be holding the schoolgirls captive.