Rescuers search for missing submersible near Titanic wreck

BOSTON - Rescue teams raced against time on Tuesday in their search for a tourist submersible that went missing near the wreck of the Titanic with five people on board.

One of the passengers on board has been identified as British businessman Hamish Harding, whose aviation firm had posted on social media about his expedition.

The 6.5m craft, operated by OceanGate Expeditions, began its descent to the wreck on Sunday but lost contact with the surface less than two hours later, according to authorities.

The US Coast Guard had launched two planes to survey the remote area in the North Atlantic, while its Canadian counterparts had sent a plane and a ship.

Time is a critical factor. The vessel has a range of 96 hours for the crew of five, and Mauger said Monday afternoon that he believed it still had 70 or more hours of oxygen remaining.

READ: Rescue teams race to find submersible missing near Titanic wreck

"It is a challenge to conduct a search in that remote area, but we are deploying all available assets to make sure that we can locate the craft and rescue the people on board," US Coast Guard Rear Admiral John Mauger told reporters in Boston on Monday.

But with no reported sightings of the vessel or communication signals throughout the day, the US Coast Guard halted its flights for the day.

It said search operations through the night would be led by the US national guard and the mission's operator.

The Coast Guard added that searches by Canadian aircraft, which were using buoys to scan underneath the surface, would continue on Tuesday morning.

An OceanGate Expeditions spokesperson told AFP in a statement late Monday that "for some time, we have been unable to establish communications with one of our submersible exploration vehicles which is currently visiting the wreck site of the Titanic."

"Our entire focus is on the wellbeing of the crew and every step possible is being taken to bring the five crew members back safely."