An Australian ship is hot on the heels of a suspected pirate fishing trawler it has been chasing for two weeks.
A good catch of endangered toothfish far outweighs later fines
The Viarsa is believed to be carrying a huge cargo of illegally poached Patagonian Toothfish - a rare delicacy that can be worth up to $23.50 a kilo.
The Australian fisheries patrol ship, the Southern Supporter, has chased the Viarsa for more than 1,900 nautical miles but has now caught up with the vessel.
But the crew of the Viarsa is refusing to allow the authorities to board and is powering away at high speed.
The Southern Supporter has an inflatable boat which the crew had intended to run up alongside the Viarsa, which is now thought to be 1,100 nautical miles
southwest of Cape Town.
But a combination of the high seas and hostility from the Uruguayan-registered trawler has prevented that from happening.
A South African ship, the SA Agulhas, complete with armed men and a helicopter, is also closing in on the ship from another direction.
The South African authorities are hoping to board the Viarsa by helicopter as soon as this weekend.
They say the ship's crew will then be arrested and charged with the illegal poaching of the rare fish.
The endangered Patagonian toothfish, sells for enormous prices in American and Japanese markets, where it is called Chilean sea bass.
The Patagonian Toothfish can command huge prices (Caroline Raymakers)
The United States has said it will stop any of the ship's suspected catch from passing through its ports.
Australian Fisheries Minister Ian Macdonald said: "The support offered by the United States, South Africa and
other nations will send another strong message to ship
masters and companies involved in toothfish poaching that the
risks of apprehension are growing rapidly."
The Viarsa, a long-line trawler, was first seen inside Australia's fishing zone about 4,000 kilometres (2,500 miles) south-west off the coast 10 days ago.
It repeatedly ignored radio orders to stop.
The Patagonian toothfish lives mainly in Antarctic waters and can reach more than two metres in length.
It lives for up to 50 years and does not breed until it is at least 10 years old.
The Australian Government warned in 1998 that the continuation of pirate fishing at present levels would mean the toothfish could become commercially extinct within two or three years.
Conservationists warned in 2001 illegal, unreported and unregulated catches were running at four times the level scientists had thought.