Story highlights "We feel that they are still alive," one relative said

The crew's air supply would have run out by now, navy spokesman said

(CNN) There is "no chance of survival" for the 44 crew members aboard the missing Argentine submarine, a navy official said Friday, one day after his agency called off its rescue operation and shifted focus to recovering the wayward vessel.

"Given ... the amount of time that has passed, the extreme and adverse conditions that I have been discussing, we have inferred that there is no chance of survival," spokesman Enrique Balbi said.

Still, the search for the ARA San Juan, he said, remains an "active one" more than two weeks after it disappeared off Argentina's coast.

"We are using all means at our disposal, both national and foreign, in the search," Balbi said. "This will obviously be key in order to conduct our investigation."

Balbi had been circumspect Thursday about the crew's fate when he announced the end of the rescue mission, though he noted that the navy had allowed nearly double the amount of time it would have been possible for the crew to stay alive if the submarine remained submerged. Officials earlier had said the submarine had enough air to last seven to 10 days.