Officials Stumped on What Might Be Causing 'Banging Sound' Near Titanic Search Site

OceanGate’s Titan submersible initially set out with five passengers onboard with hopes to view the Titanic wreckage site; however, the vessel lost contact with its support ship on Sunday, after an hour and 45 following its initial dive.

The desperate search for a submarine that has been missing since Sunday detected noises for the second day on Wednesday, however, officials remain unsure as to what might be causing the sounds.

On Tuesday night, the US Coast Guard said a Canadian search plane detected noises underwater in the designated search area. Then on Wednesday, they continued to hear noises, said Coast Guard Captain Jamie Frederick.

"With respect to the noises, specifically, we don't know what they are, to be frank with you," Frederick said at a Wednesday briefing. "We're searching in the area where the noises were detected."

According to Frederick, the team has at least two remotely-operated underwater vehicles “actively searching” for the missing submarine while several more were reported to be joining the search on Thursday. Additional search flights are continuing throughout the day and evening.

Carl Hartsfield, of the Woods Hole Oceanographic Institution, has said the noises were described as banging noises, adding that it is difficult to discern the source of noises underwater.

"They have to put the whole picture together in context and they have to eliminate potential manmade sources other than the Titan," Hartsfield said. "...The team is searching in the right area, so if you continue to do the analysis, look for different patterns and search in the right area, you're doing, you know, the best you possibly can do with the best people on the case."

The five people on the missing 22-foot submarine include OceanGate CEO and founder Stockton Rush, whose company owns and operates the Titan submarine in question, according to reports. The others include British billionaire Hamish Harding, French diver Paul-Henri Nargeolet, Pakistani businessman Shahzada Dawood and his son Sulaiman Dawood.

The submarine lost contact about 900 nautical miles off the coast of Cape Cod, Massachusetts and had been expected to resurface on Sunday afternoon. The search area, according to Frederick, has expanded to about twice the size of Connecticut with a 2 and a half mile depth.