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MAR DEL PLATA, Argentina — Argentina's navy insisted Saturday that a missing submarine had seemed to be in good condition when it set off on a training mission, despite fears it later exploded beneath the sea with 44 crew members aboard.

Hopes for survivors, already largely crushed by reports of an explosion, dimmed further as the ARA San Juan entered its 10th day missing — which is what experts had said would likely be the limit of its oxygen supply even if it remained intact beneath the sea.

But a multinational search and rescue effort continued Saturday, as a Norwegian ship carrying a U.S. undersea rescue module prepared to weigh anchor for the search zone, despite worsening weather.

A relative of missing submarine crew member Celso Oscar Vallejo kneels in prayer in front of the Mar de Plata Naval Base, Argentina, Saturday, Nov. 25, 2017. Esteban Felix / AP

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The German-built diesel-electric submarine set off on Nov. 8 from the southernmost port of Ushuaia en route to Mar del Plata.

"Two days before setting sail, there was a check of the whole operating system," navy spokesman Enrique Balbi said as a news conference on Saturday. "The submarine doesn't sail if that's not done. If it set off from Ushuaia, it was because it was in condition to do so."

Balbi said the captain reported on Nov. 15 that there had been an electrical problem in a battery compartment. But he later communicated by satellite phone that the problem had been solved and that he would continue the voyage submerged toward Mar del Plata.

Since then, there has been no contact with the San Juan, and no signs of the ship or debris despite an intensive search.

But it was also on Nov. 15 that both the U.S. Navy and the international nuclear test ban monitoring agency detected what appeared to be an undersea explosion in the area where the sub was operating.

Relatives of crew members have suggested that the 33-year-old vessel, which was refitted in 2014, was in poor condition.

Hundreds of people from Mar del Plata gathered outside the naval base on Saturday to express solidarity with relatives of the crew, applauding them and shouting, "Be strong, we are with you."

Then they joined in singing the national anthem, and many embraced.

The demonstration cheered some.

"We feel supported by the people," said Zulma de Vallejos, mother of crew member Celso Oscar Vallejos. "I know my son is going to return. I know that he will come back alive. The final word hasn't been spoken."