Another Stolt-run tanker has become the latest vessel to be hijacked off the coast of Somalia.

The 33,209 dwt chemical/product tanker Stolt Strength was transiting the Gulf of Aden “within the recognised Coalition corridor” when it was seized by Somali-based pirates, said charterer Stolt Tankers BV.

Stolt Strength, with a crew of 23 Filipinos, was Kandla-bound with a cargo of phosphoric acid from Dakar.

The tanker was boarded by armed men with automatic rifles and rocket-propelled grenades on Monday, said the International Maritime Bureau (IMB).

According to an IMB spokesman, total attacks in the Gulf of Aden off the Somali coast have jumped to 83 including 33 hijackings.

Somali pirates are currently holding 12 ships with some 200 crew as hostages, the spokesman was quoted saying.

The first Stolt-chartered tanker to be hijacked in the Gulf of Aden was the Hong Kong-flagged 25,269 dwt Stolt Valor in September.

It had 22 crew onboard, was partially laden with cargo en-route from the Suez to Mumbai, sailing in the recommended maritime security corridor when it was attacked and seized by armed pirates some 38 miles off the Yemeni coast.

According to reports, the last few days alone saw multiple incidents of piracy in the Gulf of Aden, including attacks on an Indian bulk carrier on Tuesday and a Saudi-flagged reefer cargo ship on the same day the Stolt Strength was seized.

Hijackers have also seized a ship managed by Denmark's Clipper Group with 13 crew members last week.

The 13 crew members of the Bahamas-flagged Danish-registered general cargo vessel MV CEC Future includes eight Russians, four Estonians and one Georgian.

Last week also saw pirates firing on a Maersk chemical/product tanker in the Gulf of Aden on Sunday, although the Danish-flagged ship managed to avoid being hijacked.