H.M.S. Beagle, under the command of Pringle Stokes and accompanied by the Adventure, a storage ship commanded by Captain Phillip Parker King, set sail on its first survey mission to South America.

Last year a hijacked Ukrainian ship with a cargo of tanks bound for South Sudan was also carrying 10,000 AKs and ammunition, according to the Small Arms Survey, a Swiss-based pressure group.

On Thursday, Vietnam alleged a similar incident in the zone, saying a Chinese fishing boat rammed the cables of another oil survey ship in a "premeditated" attack.