A submarine used to take tourists to view a wreck of the Titanic has gone missing in the Atlantic Ocean.
A search and rescue mission is currently underway. Adventure company OceanGate Expeditions confirmed there were people onboard the vessel.
The US CoastGuard has reportedly said there were five people onboard the vessel when it disappeared. It is reported a Brit is among those missing.
Paying tourists can take trips in small submarines to see the sunken wreck of the Titanic.
The famous wreck, which sits 12,500ft below the surface of the Atlantic, is around 370 miles off the coast of Newfoundland, Canada.
After its discovery in 1985, the wreck has been extensively explored by divers and submarine crews.
Last year, it was reported that one such excursion run by OceanGate Expeditions cost a group of guests $250,000 to take the submersible 2.4 miles down to where the wreckage lays on the seabed.
Last year's mission was 10 days long, with eight of those days at sea, a tourist brochure read. Each mission has just six people on board, known as "mission specialists".
An OceanGate Expeditions statement read: "We are exploring and mobilizing all options to bring the crew back safely. Our entire focus is on the crewmembers 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 reestablish contact with the submersible.
"We are working toward the safe return of the crewmembers."
Journalist Steve Norris added that attempts to contact the submarine had proven unsuccessful.
"U.S. CoastGuard (Boston) says there are FIVE (5) PEOPLE ONBOARD," he tweeted.
"The missing sub is believed to be in 12,500 ft of water near Titanic wreckage. It was supposed to return to Newfoundland tomorrow June 20, but all communications have been lost. Company’s website has crashed."
Earlier this year, the company said it planned an expedition to the wreck for Summer 2023, which would further document the Titanic and its "rate of decay".
Their mission plan reads: "Given the massive scale of the wreck and the debris field, multiple missions performed over several years will be required to fully document and model the wreck site.
"This longitudinal survey to collect images, videos, laser, and sonar data will allow objective assessment of the rate of decay and documentation of the process.
"Qualified explorers have the opportunity to join the expedition as Mission Specialist crewmembers whose Training and Mission Support Fees underwrite the mission, the participation of the science team, and their own training.
"Each team of 6 Mission Specialists will join the expedition for a 10-day mission (8 Days at Sea). The entire expedition is comprised of 5 mission legs."
The statement goes on to say that mission specialists would "capture data and images for the continued scientific study of the site", '"document the condition of the wreck with high-definition photographs and video", and "document the flora and fauna inhabiting the wreck site for comparison with data collected on prior scientific expeditions to better assess changes in the habitat and maritime heritage site.
The “unsinkable” passenger liner struck an iceberg four days into her journey, opening up five of her sixteen watertight compartments to the sea.
Designed to be the ultimate in luxury transport for its wealthier patrons – and help transform the lives of those emigrants looking to establish a better life in North America − 1,514 of the 2,224 passengers aboard perished in the freezing surroundings in history’s most notorious disasters at sea.
Mirror has contacted Coastguard and Oceangate Expeditions, which runs the visits.
