A large search and rescue has been established for a tourist submarine which went missing while on a dive to the Titanic wreckage on Sunday.
The US Coast Guard lost contact with the sub around one hour and 45 minutes into the dive.
There are five people believed to be onboard the vessel.
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A number of agencies have joined in the search including the Canadian and US navies and commercial deep-sea firms.
According to officials, the missing vessel is a large OceanGate Titan submersible with a four-day supply of oxygen onboard.
US Coast Guard’s John Mauger said emergency search and rescue teams only have a short window to locate the vessel.
“We anticipate there is somewhere between 70 and the full 96 hours available at this point,” he said.
Mr Mauger said that while submarines and other deep-sea vessels have been deployed to assist with the search, the area is “remote” which makes the rescue more difficult.
Tickets for the eight-day trip including the dive to the Titanic wreckage can be purchased for $250,000.
Among the people missing is 58-year-old British billionaire Hamish Harding.
OceanGate have since released a statement thanking all agencies for assisting with the search.
“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,” the company said.
The submersible is believed to be carrying one pilot, three guests and a content expert.
The vessel is comparable to the size of a truck and takes around eight hours to complete the dive including descent and ascent.
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