Got some context: Those soldiers were part of the outer siege [more precisely at the beginning of Rua de Serpa Pinto] to the crowd-packed Largo do Carmo where

Got some context: Those soldiers were part of the outer siege [more precisely at the beginning of Rua de Serpa Pinto] to the crowd-packed Largo do Carmo where Marcello Caetano (the successor to Salazar) went to seek refuge from the rebellion - inside the GNR (sort of Gendarmerie) barracks there. Portuguese state broadcaster RTP has a documentary called “Os Olhos da Revolução” about the ‘lost footage’ of the Revolution. ca. 28m53s: https://www.rtp.pt/play/p13273/os-olhos-da-revolucao https://www.rtp.pt/play/p13273/os-olhos-da-revolucao (the whole thing is worth to watch ;)