A 104-km stretch of the Mississippi River has been closed to all water traffic after two vessels collided and caused an oil spill, authorities said Sunday. The U.S. Coast Guard said in a news release that the oil spill occurred late Saturday when a tank barge collided with a tugboat near Vacherie, between New Orleans and Baton Rouge in Louisiana. No injuries were reported in the crash, but the damage to the barge caused light crude oil to spill, according to the release. It added that the source of the spill was secured Sunday, but part of the Mississippi River, including the Port of New Orleans, remained closed to avoid possible contamination of passing vessels and reduce the amount of oil spreading further down the river. A helicopter was used to help assess how much oil was spilled. The Coast Guard said the amount has yet to be determined. A unified command including the Coast Guard, the Louisiana Oil Spill Coordinator's Office, and the Louisiana Department of Environmental Quality was cooperating on the response to the spill, according to the Coast Guard..