This photo released by the French Navy shows pirates holding their hands up to soldiers, left, of the French vessel La Somme, early Wednesday Oct.7, 2009 off the Somalia coast. Somali pirates in two skiffs fired on a French navy vessel early Wednesday after apparently mistaking it for a commercial boat, the French military said. The French ship gave chase and captured five suspected pirates.(AP Photo/Olivier Amalvict/ECPAD/French Navy) ** NO SALES

London - Pirates have attacked and looted a tanker off the coast of Nigeria, taking five crew members hostage, the ship's operating company said on Wednesday.

Medallion Marine did not give the nationalities of those kidnapped but maritime security experts AKE said in a note to its clients that they were all Indians.

Piracy and kidnapping in Nigeria's oil-producing Delta and offshore are common, and the oil-rich Gulf of Guinea is second only to the waters off Somalia for the risk of pirate attacks, which drives up shipping insurance costs.

“On Monday the vessel (SP Brussels) was boarded by heavily armed pirates whilst approximately 40 miles (65 km) off the Niger Delta,” Medallion Marine said in a statement.

“The pirates ransacked the vessel for personal belongings and took five crew members with them on their departure.”

Nigerian Navy officials were not available for comment.

According to a maritime tracking website, the SP Brussels is a 7 600-tonne oil and chemical tanker.

Nigeria is a busy oil shipping route. The West African country is among the world's top 10 crude oil exporters and imports around 80 percent of the fuel products needed for its 160 million people due to a lack of domestic refining capacity.

AKE said on Wednesday the risk of maritime kidnapping is currently heightened off the Niger Delta.

Gunmen kidnapped four foreigners, believed to be South Koreans, and two Nigerians working for Korea's Hyundai Heavy onshore the Niger Delta on Monday. - Reuters