LONDON: Hamish Harding, a British businessman who collaborated with the Indian government to bring eight wild cheetahs from Namibia to India, is among five people who went missing in the Atlantic Ocean aboard a tourist submersible on a mission to view the wreckage of the iconic ocean liner the Titanic.
British-Pakistani billionaire businessman Shahzada Dawood and his son Suleman were also on the sub, the BBC reported on Tuesday.
Contact with the small sub was lost about an hour and 45 minutes into its dive in the mid-Atlantic on Sunday.
OceanGate Expeditions, a company offering eight-day missions to see the Titanic debris for USD 250,000 per person, confirmed that its submarine was lost at sea with crew members on board.
The company's chief executive, Stockton Rush, previously described the craft as "rock solid", is also believed to be on board.
The company said in a statement that it is "exploring and mobilising all options to bring the crew back safely."
French explorer Paul-Henry Nargeolet is also thought to be on board, according to a Facebook post by Harding before the dive started.
Harding also worked on a project to launch a regular business jet service to the Antarctic, working with a company called White Desert, and also collaborated with the Indian government on a project to reintroduce eight wild cheetahs from Namibia to India in September last year, under the auspices of the Explorers Club.
He had arranged a customised Boeing 747-400 aircraft for the mission.
Harding is known for his exploratory escapades across the globe.
The trip to Titanic's wreckage was the latest in a string of adventures.
He has visited the South Pole multiple times, flown into space in 2022 onboard Blue Origin's fifth human-crewed flight, and set three world records - including the longest time spent at full ocean depth during a dive to the deepest part of the Mariana Trench.
Over the weekend, Harding said on social media that a ship had set off from the city of St John's, in Newfoundland, Canada, for the destination of the Titanic wreck.
From there, he and the crew were planning to start diving operations in the submersible down to the wreck at around 04:00 local time on Sunday morning.
He wrote on Facebook that he was "proud to finally announce" that he would be aboard the mission to the wreck of the Titanic.
Due to the "worst winter in Newfoundland in 40 years," he said, "this mission is likely to be the first and only manned mission to the Titanic in 2023".
"A weather window has just opened up and we are going to attempt a dive tomorrow."
Action Aviation said on Sunday that the sub had had a successful launch and Harding was "currently diving".
Later, his stepson Brian Szasz said in a now-deleted post on Facebook: He "has gone missing on (the) submarine."
Patrick Woodhead, the founder of British tour operator White Desert Antarctica, said Harding was an "incredible" aviation explorer and a great advocate for discovering new pathways to make the world a better place.
Harding had travelled with them to Antarctica a number of times, he said, including with US astronaut Buzz Aldrin.
On an inquiry about Harding, a spokesperson from the UK's Foreign Office said it was "in contact with the family of a British man following reports of a missing submarine off the coast of North America."
In a statement released on Tuesday, the Dawood family in Pakistan said: "Our son Shahzada Dawood and his son, Suleman, had embarked on a journey to visit the remnants of the Titanic in the Atlantic Ocean. As of now, contact has been lost with their submersible craft and there is limited information available," BBC quoted the statement as saying.
The Dawood family, who live in Surbiton, southwest London, are in Canada for a month.
Shahzada Dawood, from one of Pakistan's richest families, is a trustee of the Seti Institute, a research organisation in California, according to its website.
It says he lives in the UK with his wife, Christine, and his children Suleman and Alina, and is in the Founder's Circle of the British Asian Trust.
He is also vice chairman of Dawood Hercules Corporation, part of the Dawood Group, a conglomerate of various businesses owned by the family.
In their statement, his parents said: "We are very grateful for the concern being shown by our colleagues and friends and would like to request everyone to pray for their safety."
It went on to say the family was well looked after and were praying for the safe return of their family members.
Military planes, a submarine and sonar buoys have so far been used in the search for the vessel.