>On 23 November the Argentine Navy said an event consistent with an explosion had been detected, on the day the submarine lost communications, by CTBTO seismic anomaly listening posts on Ascension Island and Crozet Islands
>The organization had been asked to analyse data from the search area by the Argentine government on the week of the disappearance, but no leads had materialised until 22 November when the CTBTO informed the government.
>The Navy added that it received information on the explosion on the afternoon of 22 November, adding that it would have concentrated search efforts in that area had it known sooner.
https://en.wikipedia.org/wiki/Disappearance_of_ARA_San_Juan
>On 23 November the Argentine Navy said an event consistent with an explosion had been detected, on the day the submarine lost communications, by CTBTO seismic anomaly listening posts on Ascension Island and Crozet Islands
>The organization had been asked to analyse data from the search area by the Argentine government on the week of the disappearance, but no leads had materialised until 22 November when the CTBTO informed the government.
>The Navy added that it received information on the explosion on the afternoon of 22 November, adding that it would have concentrated search efforts in that area had it known sooner.