The hostages were taken by members of the Nigerian radical Islamic group last month in Cameroon near the northeastern border with Nigeria, Radio France Internationale reported.
Four of the hostages are under the age of 12, the report said.
"As part of our own policy, we don't pay ransom to terrorists," said Nigerian Foreign Minister Olugbenga Ashiru. "We cannot divulge information or detail. We need to be both determined and discreet."
An eighth person from France, an engineer, is also being held captive by Boko Haram -- in Nigeria's northern Katsina state. He was kidnapped in December.
French Foreign Minister Laurent Fabius met with Nigerian President Jonathan Goodluck to discuss the abductions.