Gibraltar authorities said Friday that 80 percent of the diesel from a damaged and partly sunken bulk carrier ship has been removed but that some 180 tons of heavy fuel oil is still on board.
The ship was ordered beached after colliding Monday with another vessel in the bay of the British territory located at the western entrance to the Mediterranean Sea.
A government spokesman said there had been no further seepage of heavy fuel since Thursday and that the situation was under control.
The spokesman, who was not authorized to be named publicly, said the ship had been carrying 250 tons of diesel and still had 183 tons of heavy fuel oil and 27 tons of lubricant oil in its tanks.
The heavy fuel oil is potentially more damaging to the environment and more difficult to extract, raising concerns in Spain and Gibraltar for marine life and tourism in the area.
The spokesman said there may be announcement later Friday as to when salvage will begin working on removing the fuel.
An aerial photo of the stricken ship showed a slick on the outside of the booms placed to contain it. Officials in the nearby Spanish town of La Linea said they would study legal action if the oil reaches the coast.
The environmental impact or the quantity of oil spilled was not immediately clear. Divers sent to the ship have already sealed the source of the leak.
The usually busy port of Gibraltar remains closed, but the neighboring Algeciras port in Spain is fully operational.
The 178-meter (584-foot), Tuvalu-registered OS 35 was carrying a cargo of steel bars.
The LNG carrier with which it collided sustained little damage. No one was injured in the collision.
The captain of the damaged ship has been detained for allegedly not obeying Gibraltar port orders initially after the collision.
