The missing Titanic submarine wreckage expedition carrying five people has been missing since Sunday after disappearing 370 miles off the Canadian coast.
The US Coast Guard confirmed it was searching for the missing vessel after the Canadian research ship MV Polar Prince lost contact with the submarine 900 miles east of Cape Cod, Massachusetts.
The submarine is said to have lost contact with its support ship an hour and 45 minutes into what normally takes a two-and-half-hour dive to the bottom, where the Titanic is located.
The wreck of the Titanic is located around 370 miles off the coast of Newfoundland, Canada, and it sits 12,500ft deep at the bottom of the Atlantic.
The remains of the Titanic were discovered in 1985, and the site of the wreckage has been explored by archaeologists and marine biologists as well as tourists.
Hamish Harding and father and son Shahzada Dawood, 48, and his son Sulaiman Dawood, 19, were on board the submarine, according to Action Aviation, a company for which Mr Harding serves as chairman.
Rear Admiral John Mauger, from the US Coast Guard, admitted it is a "challenge" to try and locate the craft and rescue the passengers on board.
The wreckage lies in two parts, with the bow and the stern separated by around 2,600ft and a huge debris field surrounds the broken vessel.
The Titanic hit an iceberg on its maiden voyage from Southampton to New York in 1912 and of the 2,200 passengers and crew onboard, more than 1,500 died.
However, there are numerous complications that could hinder the search for the missing submarine including weather conditions, the lack of light at night and the state of the sea.
The US Coast Guard has sent two C-130 Hercules aircraft to search for the submersible on the surface of the water - with an underwater sonar search also taking place.
Mr Mauger said: “It is a remote area and it is a challenge to conduct a search in that remote area, but we are deploying all available assets to make sure that we can locate the craft and rescue the people on board."
The submarine, which is operated by OceanGate Expeditions and offers tours of shipwrecks and underwater canyons, disappeared in a section of the ocean with a depth of nearly 13,000ft.
The missing passengers are said to have between 70 to 96 hours of oxygen left as of Monday evening, according to Mr Mauger.
The initial group of tourists in 2021 paid $100,000 to $150,000 apiece to go on the trip.
OceanGate’s website had described the “mission support fee” for the 2023 expedition as $250,000 a person.
The company confirmed they are focusing on rescuing the missing passengers and reuniting them with their loved ones.
It said: “Our entire focus is on the crew members in the submersible and their families. We are deeply thankful for the extensive assistance we have received from several government agencies and deep sea companies in our efforts to re-establish contact with the submersible.”
