The US Coast Guard reports that additional noises have been heard in the hunt for a submersible that vanished on Sunday while being used to view the Titanic wreck site.
Capt Jamie Frederick stated that the US navy was assisting in the analysis of the noises because they were unsure of what they were.
According to him, rescue workers have increased the search area to twice the size of the US state of Connecticut.
On Thursday, more boats and submerged vehicles were expected to join the search.
Capt. Frederick stated during a press conference in Boston that a Canadian search plane had discovered underwater sounds on Tuesday and again on Wednesday.
The search team had then redirected its attention to the region where the noises had been heard.
Although underwater searches of the area where the noises were heard had not yet produced anything, it was still unknown what the noises were.
Search operations would also resume where the search was being conducted initially once more boats and underwater vehicles arrived, he said. About 26,000 square kilometers (10,000 square miles) of sea were being plowed.
Capt. Frederick said, "You always have hope. This is a search and rescue operation 100 percent. ".
He stated that there are currently five surface vessels actively engaged in the search and that five more are on their way to the area in about a day.
On Thursday morning, a number of additional remotely operated vehicles (ROVs) would join the two already searching underwater.
"We're looking for the location where the sounds were heard. We'll continue the search there in the morning and deploy more ROVs in the area where it was initially conducted, he said.
Rear Admiral John Mauger of the US Coast Guard earlier on Wednesday told the BBC that the submersible might only have 20 hours or less of oxygen left, based on the initial estimate of 96 hours.
We don't know how much oxygen is being consumed by each person on the sub, which is one of the factors that makes it difficult to predict how much is left, he said.
British businessman Hamish Harding, British-Pakistani businessman Shahzada Dawood and his son Suleman, former French navy diver Paul-Henry Nargeolet, and OceanGate CEO Stockton Rush are all present on the 21-foot vessel.
The crew would know how to maximize their oxygen supply, according to Oisin Fanning, who has previously traveled to the Titanic wreck by deep sea and knows some of the people on board the missing submersible.
According to Mr. Fanning, those on board have undergone extensive training and "will immediately look to conserve oxygen.". ".
They will exert every effort to maintain their composure, breathe rapidly, and hold onto the oxygen as long as they can, he said.
