The U.S. coast guard is allaying fears a sunken oil drilling rig off the Louisiana coast might be leaking. The rig, roughly 80 kilometres off the coast, was devastated by an explosion on Tuesday, eventually collapsing on Thursday. But while there is a significant amount of oil on the surface, Mike O’Berry, a senior chief petty officer with the coast guard, says robots show there are no leaks happening under water. Meanwhile, rescue efforts are still underway to recover 11 rig workers who are still missing since Tuesday’s explosion. More than 100 workers escaped the accident, which critically injured four.