By Elise Hammond, Maureen Chowdhury and Mike Hayes, CNN
US Coast Guard Rear Admiral John Mauger said that the submersible has 96 hours of emergency oxygen on board, based on information received from the vessel operator.
The Coast Guard "anticipate that they're somewhere between 70 to the full 96 hours" of oxygen available on the vessel at this point, he said during a news conference Monday.
Right now the Coast Guard said its priority is locating the missing submersible that didn’t emerge on Sunday after an expedition to the Titanic wreckage.
Rear Adm. John Mauger, the commander of the First Coast Guard District that is in charge of operations, said that if crews do find the vessel in the water, then rescue plans will be formed.
Mauger said the Coast Guard is "reaching out to different partners within the US Navy, within the Canadian Armed Forces and within private industry to understand what underwater rescue capability might be available."
The US Coast Guard is not releasing the names of the five people on board the missing submersible as they are still in the process of notifying families, an official said Monday.
"At this point, I'm not in a position to confirm the identity of anybody on board the vessel. Out of respect for the families, we're going, you know, through the notification process and more updates will be forthcoming," said Rear Adm. John Mauger, commander of the First Coast Guard District.
US Coast Guard Rear Adm. John Mauger said the search for the missing submersible is complex as authorities are searching both underwater and on the surface of the ocean.
He noted that the vessel could have surfaced but may have lost communication with the tour vessel from which it launched on Sunday.
The search is incorporating aircraft, sonar buoys and "sonar on the ship that is out there to listen for any sounds that we can detect in the water column," he said.
"Over the course of the next couple of days, we anticipate adding additional capabilities to conduct additional search in the water as those commercial assets arrive on scene," Mauger added during a news conference on Monday.
The location of where search teams are looking for the missing submersible is in a remote location, said Rear Adm. John Mauger, commander of the First Coast Guard District, during a news conference Monday.
"The location of this search is approximately 900 miles east of Cape Cod, in a water depth of roughly 13,000 feet. It is a remote area and it is a challenge to conduct a search in that remote area," Mauger said during a news briefing in Boston. "But we are deploying all available assets to make sure that we can locate the craft and rescue the people onboard."
The US Coast Guard is going "everything that we can do" to locate and rescue the people on board the missing submersible that was heading toward the wreckage of the Titanic, said Rear Adm. John Mauger.
Mauger is the Commander of the First Coast Guard District, which is leading the search and rescue operation for the submersible.
During a news conference on Monday, Mauger said the Coast Guard first received a call from the operator of the vessel that the submersible was overdue on Sunday.
After that call, the Coast Guard reached out to the vessel used to transport it to the site of the Titanic wreckage before the expedition and started searching on the surface of the water, Mauger said.
At the same time, the Coast Guard launched an aircraft to start conducting aerial and radar searches, he added.
“Our thoughts are with the families and the crew members onboard this submersible," Mauger said, adding that there were five people on board.
From CNN staff
The United States Coast Guard will hold a news conference at 4:30 p.m. ET in Boston on the search for the missing submersible near the Titanic wreckage.
“The Coast Guard is searching for five persons after the Canadian research vessel Polar Prince lost contact with their submersible during a dive, approximately 900 miles east of Cape Cod, Sunday morning,” the agency said in a news release.
Rear Admiral John Mauger, Commander of the First Coast Guard District is expected to lead the briefing.
More background: The eight-day expedition is based out of St. John’s, Newfoundland, Canada, with a maximum of six people. The trip begins with a 400-nautical-mile journey to the wreck site, according to the tour operator.
There, up to five people board the submersible named “Titan” and descend to the bottom of the ocean.
From CNN’s Celina Tebor and Gabe Cohen
The missing submersible near the Titanic wreckage lost contact with a crew 1 hour and 45 minutes into its descent Sunday morning, according to the US Coast Guard.
The 21-foot submersible was carrying five people, the Coast Guard tweeted.
The submersible lost contact with the crew of Polar Prince, the vessel used to transport it to the site of the Titanic wreckage before the expedition, according to the Coast Guard.
Chief Mi’sel Joe of Miawpukek First Nation, which co-owns the Polar Prince, said he received a call Sunday afternoon from the CEO of Horizon Maritime alerting him that the submersible was two hours overdue and hadn’t surfaced.
He was told communication with the sub was lost as it was going down to the wreckage. At that point, he says, requests for search and rescue had gone out.
“There’s a tremendous amount of concern,” Chief Mi’sel Joe said. “I have anguish that people are going through this. I wish there was more I can do.”
From CNN's Eric Levenson
The expedition to explore the wreckage of the Titanic costs passengers "from $250,000," according to an archived version of the company's website, accessible via the Internet Archive’s Wayback Machine.
OceanGate Expeditions, the company that operates the tour, advertised the experience as a way "to step outside of everyday life and discover something truly extraordinary.”
“Become one of the few to see the Titanic with your own eyes," it added.
There, up to five people, including a pilot, a “content expert” and three paying passengers, board the submersible named “Titan” and descend to the bottom of the ocean.
“Once the submersible is launched you will begin to see alienlike lifeforms whizz by the viewport as you sink deeper and deeper into the ocean. The descent takes approximately two hours but it feels like the blink of an eye,” the website said.
According to OceanGate, the Titan is a 23,000-pound submersible made of carbon fiber and titanium.
As a safety feature, the sub uses a “proprietary real-time hull health monitoring (RTM) system” that analyzes the pressure on the vessel and the integrity of the structure, the company states. It also has life support for a crew of five for up to 96 hours, the website states.