A Coast Guard towing vessel collided Tuesday with an oil and natural gas platform off the coast of Louisiana, sparking a minor oil spill in a region that is already dealing with the BP oil disaster. The morning collision in Barataria Bay left a "light sheen" of oil and some natural gas vapours spilling out of the platform, said Coast Guard Admiral Thad Allen, who is coordinating the government's response to the wider BP oil disaster in the Gulf of Mexico. Allen could not say how much oil was flowing out of the platform, but played down the incident, saying "we only have indication there was a light sheen." About 1.8 kilometres of containment boom have already been placed around the platform, Allen said. The thousands of ships already in place to tackle the bigger BP oil spill meant authorities were able to react quickly to the accident.