Search and rescue crews are frantically scanning more than 12,500 feet of open water near the historic site of the Titanic wreckage as five people are missing aboard a submersible.
British billionaire and famous explorer Hamish Hamish Harding is among the five people trapped on the tourist submersible that had been on a venture down to the site - before the crew on board made no contact with the support crew for more than eight hours.
Depending on where the submersible was when it lost contact with OceanGate, the company in charge of the mission, it could theoretically be anywhere within a 370-mile stretch of the Atlantic Ocean between the wreck and the Newfoundland, Canada, coast.
It is believed to be near the wreckage, however, according to journalist Steve Norris — and that's where crews are focusing their search for the vessel, which the US Coast Guard confirmed was carrying five people.
A map which is hosted on OceanGate's website, shows the location of the RMS Titanic wreck, relative to St John's and Newfoundland, where the submersible was heading before it lost contact.
In an update tonight, the US Coast Guard said it was it was “searching for an overdue Canadian research submarine approximately 900 miles off Cape Cod.”
A Boeing P-8 Poseidon maritime patrol and reconnaissance aircraft had been flown to the area from the “rescue coordination centre Halifax” to help in the search.
The missions, which generally last between eight and 10 days, begin near St. John's, Newfoundland, Canada.
Crews then travel to the wreck, which is located 370 miles south of the island and approximately 2.4 miles under the surface.
A map on OceanGate's website shows the path crews usually take to visit the wreckage.
The sub went missing on Monday morning, and so far, attempts to contact the crew by the US Coast Guard have been unsuccessful.
Each vessel is different, according to Parks Stephenson, the technical director on James Cameron's Titanic film and an expert on the Titanic and submersible vessels that explore wrecks like it.
But in general, it takes approximately two hours for them to submerge and another two for them to surface, he told Radio 4's PM programme.
He said the loss of communication is a "highly unusual event."
But who are the five people on board the vessel? And what are their chances of survival?
Information has not yet been officially released about their identities, but one is confirmed to be famous British explorer Hamish Harding.
The billionaire is no stranger to extreme adventures.
He has been to the South Pole twice, into space on Jeff Bezos’s Blue Origin Rocket and a dive to the Challenger Deep, the deepest place on Earth at the bottom of the Pacific Ocean.
Tonight his stepson, Brian Szasz, wrote on Facebook: "Thoughts and prayers for my Mom and Hamish Harding."
He added: "Hamish Harding, my stepfather, has gone missing on submarine thoughts and prayers."
Mr Harding holds several world records, including the fastest circumnavigation of the globe via both poles in an airplane as well as the greatest duration spent at full ocean depth for a trip he took to the bottom of the Mariana Trench in 2021.
The Mirror has contacted the US Coast Guard and OceanGate for more information.
