Pakistani authorities are struggling to empty a Greek oil tanker grounded outside Karachi before it breaks up even further.
Karachi's beaches have been destroyed
The tanker has already leaked more than 25,000 tonnes of oil into the Arabian Sea, polluting Karachi's coastline and killing marine life.
Some 37,000 tonnes of crude have been drained from the tanker - the Tasman Spirit - which has been stranded in the country's main port since 27 July.
But there are fears the rear section could break in two as cracks have developed in the hull.
"If that rear portion breaks, the bulk of the remaining oil will also spill. We are fighting against time to empty the ship before that happens," a Karachi port official said.
Residents near the beach and adjacent islands have complained of
headaches, nausea and respiratory problems, doctors say, while many Karachi restaurants have stopped serving seafood.
The Tasman Spirit was carrying around 67,500 tonnes of crude when it ran aground in bad weather and a high monsoon
tide. It later split in two.
A small salvage tanker sent by the
United Arab Emirates has arrived to help with the delicate
Environmentalists say it will take months to clean and
restore Karachi's beaches which are now covered with a thick layer of black
crude and littered with dead fish, turtles and sea snakes.
The Greek and Filipino nationals sailing the stricken tanker have been interrogated by the authorities.