SINGAPORE - The busy waterways off Singapore's coast play host to numerous ships, and there have been occasional collisions, some of which had led to oil spill.
Three occurred in the space of two weeks in 2014, while a major spill closed beaches at Changi for a week in 2010.
Here is a look at some of the major ones in the past two decades.
Feb 11, 2014
It was the third oil spill in two weeks.
Some 80 metric tonnes of bunker fuel was poured into the Singapore Strait off Sebarok Island.
The Liberia-flagged container ship, Hammonia Thracium, and the Panama-flagged chemical tanker, Zoey, collided about 10km south of the mainland.
Jan 30, 2014
A collision between Panama-flagged container ship NYK Themis and a barge, AZ Fuzhou, occurred at the East Keppel Fairway, about 4km south of Marina South.
The barge was being towed by a tug at the time. One of NYK Themis' bunker tanks was damaged, resulting in 400 tonnes of fuel oil being spilled.
Jan 29, 2014
The first spill of 2014 occurred on Jan 29, when Hong Kong-flagged chemical tanker Lime Galaxy collided with China-flagged container ship Feihe about 2.7km south of Jurong Island.
Some 280 tonnes of fuel oil slicked the shores of some southern islands.
May 25, 2010
Beaches in Changi, East Coast Park and Pasir Ris were closed for more than a week after a collision of two large vessels off Changi resulted in an oil slick.
The accident involved Malaysian-registered tanker MT Bunga Kelana 3 and the MV Waily, a bulk carrier registered in St Vincent and the Grenadines.
Some 2,500 tonnes of oil were dumped 13km off the Changi coast.
The oil spill subsequently spread to Chek Jawa - a protected 100ha wetland off Pulau Ubin.
June 12, 2003
A Singapore-registered ship spilled about 150 tonnes of fuel oil when it ran aground near Horsburgh Lighthouse in the eastern approaches of the Singapore Strait.
The MV APL Emerald, a 40,077-tonne container ship, hit some rocks about 1.3km south of the lighthouse on Pedra Branca.
The spill was contained and did not reach Singapore's shores, which are about 46km away.
Oct 3, 2000
A Panama-registered oil tanker, Natuna Sea, ran aground in Indonesian waters off Batu Berhanti Beacon, just 8 km from Sentosa.
The incident resulted in 7,000 tonnes of oil spilled and the slick reached beaches of Sentosa, St John's Island and the adjacent Pulau Sakijang.
Oct 15, 1997
Thai-registered crude-oil tanker Orapin Global collided with Cyprus-registered tanker Evoikos resulting in possibly Singapore's worst oil spill.
More than 28,000 tonnes of marine fuel oil spilled into the sea when two tankers collided in the Singapore Strait.
It took 650 men and 90 anti-pollution craft three weeks to clean up.