The US Coast Guard has confirmed that an aircraft taking part in the hunt for a lost submersible in the North Atlantic has heard sounds underwater.

According to an internal government memo cited by a number of US media outlets, sonar detected banging at 30-minute intervals during the search for the submersible that was visiting the Titanic wreckage.  

US Coast Guard Northeast stated on its official Twitter account that while some operations had been moved to look for the noises, nothing had been found as of yet.

The US Navy is also analyzing the information.  

Hamish Harding and Paul-Henri Nargeolet are members of the Explorers Club, which acknowledges that there are probably "signs of life." 

Richard Garriott do Cayeux, the club's president, said they had "greater confidence" as the search for the submersible went on. The club is a multidisciplinary professional society based in New York that supports scientific exploration. 

In a statement, he said, "We are so grateful that the US Coast Guard, as well as other international teams and commercial operators, are doing everything they can to assist from the Titanic expedition submersible."