Search and rescue crews remotely operating an underwater vehicle discovered a “debris field” near the Titanic while looking for a missing tourist submersible carrying five people, the U.S. Coast Guard said Thursday, the day the small vessel is expected to run out of oxygen.

“A debris field was discovered within the search area by an ROV near the Titanic. Experts within the unified command are evaluating the information,” the Coast Guard wrote on Twitter.

The debris was discovered by a remotely operated vehicle (ROV) associated with the Canadian vessel Horizon Arctic that reached the sea floor and began searching for the submersible early Thursday, according to the branch. The Coast Guard scheduled a news conference on the development at 3 p.m. ET in Boston.

The accelerating search efforts come as an updated prediction by the Coast Guard said the Titan submersible was likely to run out of oxygen roughly around 7 a.m. ET Thursday. It initially had 96 hours of oxygen for a crew of five. Experts have noted that the estimates are imprecise.

“People’s will to live really needs to be accounted for as well, so we’re continuing to search and proceed with rescue efforts by bringing this new capability online this morning,” Rear Adm. John Mauger of the U.S. Coast Guard told the TODAY show early Thursday.

The ROVs on site are able to attach rescue lines, and personnel with deep-sea medical expertise are moving onto the scene, he said. Teams worked through the night, he said.

“We’re going to continue searching throughout the day,” Mauger said.

The 22-foot vessel was on a dive to the site of the Titanic wreckage when it lost contact with its support ship Sunday. On board are a British explorer, a father and son from a prominent Pakistani business family, a French Titanic expert and the CEO of OceanGate, the Washington state-based company that operates the vessel.