Rescuers 'exponentially' expanding search for missing Titanic sub

MASSACHUSETTS, US - JUNE 21: The US Coast Guard said Wednesday that a multinational group of first responders is bringing in additional resources to scour above and below the ocean’s surface as the search for a missing tourist submersible dramatically expands. Capt. Jamie Frederick, the First Coast Guard District response coordinator, told reporters in Boston, Massachusetts that additional banging noises were heard early Wednesday after first being detected Tuesday. Rescuers are now "exponentially expanding the size of the search area" to include an area twice the size of the state of Connecticut and two-and-a-half miles (4 kilometers) deep. The source of the sounds detected on Tuesday has not yet been ascertained, and Frederick said experts are continuing to analyze them to determine if they are man-made or natural. Five search ships, underwater unmanned vessels (ROV) and planes are currently scouring the area for signs of the Titan, with that number expected to double to 10 by Friday at the latest, according to the Coast Guard. P-3 Poseidon and C-130 airplanes are continuing continuous searches in the area in 14 hours shifts. Personnel from Canada, France and the UK are assisting in the effort. Frederick said the ROVs, or remotely operated vehicles, were relocated in response to the sounds heard Tuesday, but "yielded negative results." Operations are ongoing. "We're focused on searching at this point. This is a search and rescue mission 100%," he said. "You always have hope." Officials said earlier that the Titan submersible had about 96 hours of oxygen for the five-person crew that disappeared Sunday. The timeline expires roughly Thursday morning, but Frederick emphasized it represents "just one piece of data." (Footage by Lokman Vural Elibol/Anadolu Agency via Getty Images)