Ecuadorean authorities said Friday they have offloaded all the fuel and most of the cargo from a freighter that ran aground in the Galapagos Islands, and it will take three to four weeks to refloat and rescue the ship.

Galapagos national park director Arturo Izurieta also told The Associated Press that it will cost about $6 million to salvage the 2,300-metric ton Galapaface 1.

The ship ran aground last week in the bay adjacent to San Cristobal, the second-most populated island of the Galapagos, with a cargo of food and other supplies. Any possible environmental disaster was largely averted with the removal of its fuel.

Izurieta said about 1,000 tons of water have filled the lower decks.

The Galapagos' unique flora and fauna helped inspire Charles Darwin's theory of evolution. They are a major tourist attraction.