Banging sounds have been detected as the search and rescue operation has now expanded into deeper waters.

According to an update posted by Rolling Stone, the U.S. Coast Guard confirmed that a Canadian aircraft has detected “underwater noises.”

As reported, the Search teams are focusing on the surface of the ocean and the seabed.

• The tiny craft lost signal in the dark depths of the Atlantic Ocean, 370 miles off the coast of Newfoundland, Canada
  
• The 21-foot craft, operated by OceanGate Expeditions, began its descent on Sunday but lost contact with the surface less than two hours later
• Shahzada Dawood, one of Pakistan’s richest men, and his teenage son are among the five people missing in the submarine that set off to see the wreck of the Titanic

As reported, the crews searching for the Titan submersible heard banging sounds every 30 minutes on Tuesday, and four hours later, after additional sonar devices were deployed, banging was still heard, according to an internal government memo update on the search.

A subsequent update sent Tuesday night suggested more sounds were heard, though it was not described as “banging.”

“Additional acoustic feedback was heard and will assist in vectoring surface assets and also indicating continued hope of survivors,” according to that update.

Read more: 2 Pakistanis on board missing submarine that went to see remnants of the Titanic shipwreck

A Canadian P3 aircraft also located a white rectangular object in the water, according to that update, but another ship set to investigate was diverted to help research the acoustic feedback instead.

This marks the first breakthrough after a three-day search and rescue operation for the truck-sized submersible.

The Titan submersible, having five people onboard, lost contact on Sunday about an hour and 45 minutes into its dive to see the Titanic wreck in the Atlantic Ocean.

As projected, the Titan’s air supply is likely to run out in around 27 hours.

British-Pakistani businessman Shahzada Dawood and his teen son Suleman are two of the five people on the missing submersible, along with British businessman Hamish Harding, retired French navy commander Paul-Henri Nargeolet, and OceanGate CEO Stockton Rush.