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March 22 (Reuters) - A barge leaked oil into the Houston Ship Channel after colliding with another ship near Texas City on Saturday and emergency responders laid down floating barriers to contain the spill, U.S. Coast Guard officials said.
Officials shut down the channel for ship traffic entering and exiting the Gulf of Mexico following the incident at the mouth of Galveston Bay, a spokesman for the Galveston County Office of Emergency Management said.
Coast Guard officials said early on Sunday they did not know when the channel might reopen.
The barge, which was being towed by the motor vessel Miss Susan, contained 168,000 gallons (636,000 liters) of fuel oil in the tank that was breached in a collision with a bulk carrier, the Summer Wind, said Coast Guard spokeswoman Petty Officer 3rd Class Manda Emery.
The barge and another barge towed by the motor vessel had a total of 924,000 gallons (3.5 million liters) of fuel oil but the other tanks on board were not breached, she said.
"This is a very significant discharge" of oil, said Coast Guard spokesman Lieutenant Junior Grade Kristopher Kidd.
Officials said it was unclear exactly how much oil spilled out of the breached tank, which has partially sunk.
Authorities have laid down floating boom lines in an effort to contain the sheen of oil on the water, Emery said.
Kirby Inland Marine, which owns the motor vessel and the barges, is involved in the emergency response, according to the Coast Guard. The barges were being towed between Texas City and Port Bolivar at the time of the collision, Kidd said.
The Houston Ship Channel is a 53-mile (85 km) waterway connecting Houston and its petrochemical port, which is the largest in the United States, to the Gulf of Mexico. (Reporting by Alex Dobuzinskis in Los Angeles and Chris Michaud in New York; Editing by Lisa Shumaker)