When the soldiers aimed Granpa and Gracielita to their flat, some soldiers in the stairs dressing like civil where hitting two teachers that where found hidden in the top of the building, meanwhile, the Grandpa and the rest of the family are watching at the door. During the fight there are some shots taking as the stairs as the door of the flat, shifts from day to night are notable in each take.
Before the military attack we see a clock with the word "Quartz" on its face. In Mexico, electronic clocks were not in common use until the 1970s.