Pirates have kidnapped two crewmen from a Bourbon anchor-handler off Nigeria.

The French owner confirmed that a Nigerian and a Russian were seized from the 80-bp Bourbon Liberty 251 (built 2011) this week, according to TradeWinds’ sister website Upstream.

The ship was attacked in the Gulf of Guinea on Tuesday.

"The 10 other crew members are back on board the vessel in Onne port, safe and sound," Bourbon said

The company has set up an emergency team and is in contact with the families of the kidnapped men.