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More ships join search for sub after report of banging noise
4m 31s
The search for the missing submersible in the North Atlantic Ocean intensified Wednesday. The day began with a surprise, reports of banging noises detected by sonar. The U.S. Coast Guard said it is still treating the mission as a search and rescue operation even as the supply of oxygen is likely dwindling for the five people aboard. Amna Nawaz reports.