Debris recovered from the submersible that catastrophically imploded while on a voyage to see the Titanic wreckage last week contained "presumed human remains," the U.S. Coast Guard said. Salvaged pieces of the Titan vessel were unloaded from the Canadian ship Horizon Arctic at the Canadian Coast Guard pier in St. John's, Newfoundland, Wednesday morning. The U.S. Coast Guard said later Wednesday it has received the debris and evidence, including "presumed human remains," that had been recovered from the ocean floor in the incident, in which five people died.