Underwater noises heard as crews race to find Titanic tourist sub

The US Coast Guard has confirmed early that rescue teams looking for the missing Titanic submersible detected "underwater noises" in the search area where the craft went missing two days earlier.

Authorities in the US and Canada are racing against the clock to locate the vessel that was carrying people to see the Titanic wreckage site in the North Atlantic Ocean.

When it went missing, the submersible had 96 hours of additional oxygen available.

"Canadian P-3 aircraft detected underwater noises in the search area. As a result, ROV (remotely operated vehicle) operations were relocated in an attempt to explore the origin of the noises," the US Coast Guard's First District said on its official Twitter page on Wednesday.

The ROV searches "have yielded negative results but continue," the maritime military branch added.

Lack of oxygen

Early on Wednesday, the US coast guard said that about 40 hours of oxygen was left in the lost Titanic tourist submersible.

"The search efforts have focused on both surface with sea 130 aircraft searching by sight and with radar and subsurface with p3 aircraft. We're able to drop in monitor sonar buoys, today, those search efforts have not yielded any results,” said Captain Jamie Frederick from the First Coast Guard District response department.

The search teams are working in an area that is 900 miles east of Cape Cod, 400 miles south of St. John's, Canada, and it takes time and coordination to bring assets to bear, which makes it an incredibly complex operation, he said.

Regarding search and rescue operations, the US Navy is “on standby should they be needed,” according to the White House.

The Navy has “some deep water capabilities that the Coast Guard wouldn't necessarily have,” National Security Council spokesperson John Kirby said in a news briefing.

Five people are on board, including Hamish Harding, a British billionaire explorer, and Paul-Henri Nargeolet, a renowned French diver.