Pirates have kidnapped nine Nigerian nationals from an offshore oil vessel, the owner BW Offshore said in a statement.
The ship, the Sendje Berge, was being repaired when the attack happened, Staale Andreassen frrom the company is quoted by Reuters as saying.
"We are working now with the Nigerian authorities to get those nine people safely back," he added.
The Sendje Berge is a floating production, storage and offloading vessel.