This undated image courtesy of OceanGate Expeditions, shows their Titan submersible during a descent. - Copyright AFP PHOTO / OCEANGATE EXPEDITIONS
Rescue crews are desperately searching for the vessel that vanished in the North Atlantic Ocean on Sunday.
Search teams are racing against the clock to find a missing submersible before the oxygen supply runs out for five crew members on board.
A Canadian aircraft looking for the sub in the Atlantic Ocean has detected "banging" noises near its last known location.
It is unclear how long the banging lasted, but the discovery was shared via email with the US Department of Homeland Security.
The US Coast Guard, which is leading the search, has relocated its rescue operation as a result of the underwater sounds, but so far has "yielded negative results".
Authorities estimate the vessel has around 30 hours of oxygen left, as of Wednesday morning.