Hundreds of search teams have swarmed an area over 1,400 km2 in search of the missing submarine, which was taking passengers to see the Titanic wreck.

Ships and planes from the United States and Canada are searching for a submarine that went missing off the coast of southeastern Canada while taking tourists to see Titanic wreckage.

A boat on the surface – the Polar Prince – lost contact with the submarine, the Titan, about one hour and 45 minutes after it began diving toward the Titanic wreckage.

Does the submarine have any passengers?

A pilot and four passengers were on board, and the vessel could be submerged for 96 hours, but it was unclear whether it was still underwater or had surfaced.

One of the passengers is British billionaire Hamish Harding, according to a relative’s post on social media.

Harding’s stepson asked for “thoughts and prayers” on Facebook after Mr Harding went missing on submarine.

A few days later, the stepson removed the post, citing respect for the privacy of the family.

Earlier this week, Mr Harding posted that he would be aboard the submarine on Facebook.

He has not posted since then.

In Harding’s post, he said the expedition left on Friday, and the first dive was scheduled for Sunday.

The submarine that went missing while taking people on tours to see the Titanic used a cheap Logitech controller and other off the shelf parts.

pic.twitter.com/b4K9YefdWQ

— Ian Miles Cheong (@stillgray) June 20, 2023

Harding holds three Guinness World Records: longest duration at full ocean depth for a crewed vessel, longest distance traversed at full ocean depth for a crewed vessel and fastest circumnavigation via both poles for an aeroplane.

In March 2021, Harding and ocean explorer Victor Vescovo performed two of these feats in a two-person deep-submergence vehicle in the Mariana Trench – the deepest point in the ocean.

He traveled to space last June with fellow billionaire Bill Gates