Urgent hunt for lost Titanic sub continues as details emerge about company's past safety concerns

Authorities are intensifying search efforts for the OceanGate submersible Titan, which went missing Sunday during a dive down to the wreck of the Titanic.

Coast Guard officials are exploring "underwater noises" that were detected through a surveillance plane equipped with sonar technology. The vessel has less than 24 hours of oxygen left in the tank, amping up the pressure to find the five lost crew members.

Here & Now's Robin Young speaks with WBUR reporter Walter Wuthmann on the latest.