Coast Guard says extensive search has yielded no sign of missing sub

This undated photo provided by OceanGate Expeditions in June 2021 shows the company's Titan submersible. On Monday, June 19, 2023, a rescue operation was underway deep in the Atlantic Ocean in search of the technologically advanced submersible vessel carrying five people to document the wreckage of the Titanic, the iconic ocean liner that sank more than a century earlier. (OceanGate Expeditions via AP, File)