Kidnappers have boarded a ship off Nigeria and abducted seven crew members, including six Russians and one Estonian, in the latest such incident in the region, French company Bourbon said on Wednesday.

"Bourbon confirms that seven crew members, six Russians and one Estonian, were kidnapped during the boarding of the Bourbon Liberty 249, which occurred on October 15, 2012 in Nigeria," a statement from the oil industry servicing firm said.

"The other nine crew members are still onboard the vessel which is heading for the Port of Onne. They are safe and sound, and in good health."

The statement did not give the location of the kidnapping, but Onne is located in the Niger Delta, the country's oil-producing region.

Scores of kidnappings for ransom have occurred in the Niger Delta, though a 2009 amnesty deal greatly reduced unrest there.