Salvage experts have abandoned attempts to refloat a blazing cargo ship that ran aground off the South African coast.

The ship - the Jolly Rubino - caught fire last week and became stranded near the Saint Lucia Wetland, an environmentally sensitive reserve recognised by UNESCO as a world heritage site.

The fire on board has spread to the engine room and the cracks in its hull are getting larger, the BBC's Alastair Leithead reports from South Africa.

Wildlife home

Saint Lucia is a sanctuary for: Hippos Crocodiles Pelicans Flamingoes Estuarine fish Mangrove forests

The operation will now centre on attempts to pump fuel out of the ship's tanks before it breaks up.

Booms have been put in place in an attempt to prevent the oil slick from coming ashore.

Smit Salvage had made an unsuccessful bid to put out the fire, which broke out a week ago, crippling the vessel and forcing the crew to abandon ship.

Weather fears

On Wednesday, the fire spread and reached the freighter's engine room.

The ship is carrying oil, petrol and a cargo of toxic chemicals.

Environmentalists have expressed concern about the impact on wildlife in the area.

This concern has been heightened by expected changes in the weather later in the week which could hasten the break up of the ship.

The Jolly Rubino ran aground about 11 kilometres (6 miles) south of the Unesco-recognised wetlands.

The sand around the ship was streaked with heavy fuel oil, and larger patches of oil have been spotted floating near the shore.

The South African authorities have said that there is an 8 km (5-mile) long oil slick in the sea near the vessel. Officials said the winds and tides were carrying the slick away from the Saint Lucia area, according to the Reuters news agency.

Ship cracked

About 400 tonnes of oil are believed to have escaped through a 20 metre crack in the ship's port side.

Crisis management officials held a brief debate over whether to declare the wreck a national disaster, but decided instead to label it a "major incident" after concluding that the situation was not yet out of hand.

The 22 crew of the Jolly Rubino were airlifted to safety last Tuesday and the ship's dog was rescued on Friday.

The ship had left Durban in South Africa for a journey to Mombasa, Kenya.

News agencies quoted a senior South African maritime official as saying that the ship could now become part of the coastline and was already attracting tourists to the area.