Transcript for Ongoing search for missing Argentinian submarine

We start with American forces joining the search for a missing submarine. The vessel from the argentinean Navy has not been heard of since Wednesday but they're holding out hope and Ron is back with more. There was a report that that sub had been spotted but that turned out so far to be unfounded so it's now three days since it disappeared off the coast of Argentina after a fire on board knocked out its communications. Still no trace of it. This morning, the desperate search for that missing submarine. The massive effort now under way off the coast of Argentina. Navy ship, planes and helicopters all looking for any sign of the submarine that had 44 crew members on board. The submarine vanishing Wednesday. It's one of only three submarines in the Argentine Navy on a routine trip off the coast of that country when it suddenly disappeared. So you have cold water, you have rough seas. It's a long way from land so it's tough to get rescue ships and airplanes out there and we have no sign and no good indication of precisely where it might be. Reporter: The government lost contact with it after a fire on board knocked out communications. According to media reports, officials say they do not yet believe it is lost. Claiming the crew has sufficient food and oxygen on board. But the clock is ticking. Because they rely on the batteries to keep them alive while they're submerged every hour that goes by means it's less chance of finding this crew aletch. Standard Navy protocol is for a submarine that loses communication to surface to be located. That's been hampered by bad weather, high winds and heavy winds. They're back at it today. Obviously a concern growing now three days after it last communicated with headquarters, still no contact. Holding out hope. Yeah. Still possible. It is. Thank you, Ron.

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