The Polar Prince, which towed the Titan submersible out to sea eight days ago, returned to St. John’s harbour early Saturday morning.

The Transportation Safety Board of Canada is launching an investigation into the fatal occurrence involving the Canadian-flagged vessel Polar Prince and the privately operated submersible Titan.

While the TSB will lead the investigation on the Canadian side, the U.S. Coast Guard will lead the investigation on the American side. The National Transportation Safety Board in the U.S. posted on Twitter that he U.S. Coast Guard has declared the loss of the Titan submersible to be a major marine casualty and will lead the investigation. The NTSB has joined the investigation and will contribute to their efforts.

On Sunday, June 18, the Canadian-flagged cargo vessel Polar Prince was at the Titanic wreck site, 325 nautical miles south-southeast of Cape Race, Newfoundland and Labrador, providing surface support to the submersible Titan. There were 17 crew members and 24 people on board the Polar Prince. Five people from the Polar Prince were on board the Titan and approximately 1 hour and 45 minutes after the submersible began its descent, the support vessel lost contact.

On June 22, the United States Coast Guard confirmed that the debris found on the ocean floor near the Titanic wreckage consisted of pieces of the missing submersible. As a result, the five people on board the Titan are presumed dead.

In accordance with the Canadian Transportation Accident Investigation and Safety Board Act and international agreements, the TSB, as the investigation authority of the flag state of the support vessel involved in the occurrence, will conduct a safety investigation regarding the circumstances of this operation conducted by the Canadian-flagged vessel Polar Prince.

A team of TSB investigators is travelling to St. John’s, Newfoundland and Labrador, to gather information, conduct interviews, and assess the occurrence. In the coming days, we will coordinate our activities with other agencies involved.

This is all the information available at this time. Updates will be provided as the investigation progresses.

See the investigation page for the latest information.