With just a few hours of oxygen likely to be left on the Titanic tourist submersible, search-and-rescue operations grew more hectic on the intervening night of June 21 and 22.
Ten ships and several remote submarines joined the effort in the northern Atlantic Ocean to locate the 21-foot mini-submarine which was used to take tourists to the sunken ship Titanic.
The search operations have been centred around the area where some underwater noises were detected on June 20 and 21.