The US Coast Guard says more noises have been heard in the search for the missing Titanic submersible.
Captain Jamie Frederick says they still don't know what the noises are but teams are still looking in that area.
The search is being expanded and the surface search is now twice the size of the US state of Connecticut, and the sub-surface search is 4 kilometres deep.
Capt Frederick also says it's still a search and rescue operation, adding they have to remain optimistic and hopeful.
The crew are thought to have less than 20 hours of oxygen left, based on a previous estimate.
Contact with the submersible which has five people on board - was lost on Monday as it made a 3,800m descent to the Titanic wreck.
Source: BBC
