The same source added that the alert to the authorities was given at 1:20 pm.
Oliver Antić was Serbia's ambassador to Portugal, Cape Verde and São Tomé and Príncipe, according to the embassy's official website.
The Serbian Ministry of Foreign Affairs confirmed on its website the ambassador's death, "following an accident".
In the note, the Serbian Government expresses its regret and highlights the "professionalism and dedication" of Oliver Antić, as well as his contribution to "the improvement of relations between Serbia and Portugal".
According to CDOS, there were four vehicles and seven operational firefighters from Estoril, the National Institute of Medical Emergency (INEM), the National Maritime Authority and the Instituto de Socorros a Náufragos.
As the commander of the Captaincy of the Port of Cascais, Paulo Gomes Agostinho, told Lusa, when the authorities received the alert of the occurrence “they did not know who it was, nor what had happened, they only knew when they arrived at the scene”.
“During the on-site resuscitation maneuvers, we learned from the witnesses, one of whom was also from the embassy, that he was the Serbian ambassador to Portugal,” he said, adding that it was the people accompanying the diplomat who said what had happened.
INEM confirmed to Lusa that it was called to help a 71-year-old drowning victim, but “the death was verified on the spot” after resuscitation attempts.