A submarine which takes tourists to see the wreck of the Titanic has gone missing in the Atlantic Ocean, sparking a widespread search and rescue mission, reports the BBC.
It's currently unknown how many people were on board the submarine at the time.
Paying tourists can take small trips in submarines to see the sunken ship, which sits 12,500ft below the surface of the Atlantic - around 370 miles from the coast of Canada's Newfoundland. Following its discovery in 1985, the wreckage has been intensively explored by divers and submariners.
Last year, it was reported that one such excursion by OceanGate set a group of guests back $250,000 to take the vessel 2.4 miles down to where the wreckage lays on the seabed. The mission was ten days long, with eight of those days out at sea, a tourist brochure read.
Read more: NASA rover discovers 'dragon bones' on Mars
The Mirror reports that each mission has just six people on board, known as 'mission specialists'. Earlier this year, the company said it had planned an expedition to the wreck for summer 2023 - which would document the Titanic and its 'rate of decay' further.
The 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 detail how 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 just four days into its journey in April 1912, opening five of its sixteen watertight compartments to the sea. A total 1,514 of the 2,224 passengers aboard perished in the freezing surroundings in history’s most notorious disasters at sea.
Read next:
