Sarah Errington, 73, was working as a photographer for the Associated Press in Saigon when members of the North Vietnamese Army stormed in on April 30, 1975. Id gone out to take pictures that morning and things were a bit strange, she recalled. We knew things were going to happen quite fast. On that day, the dark room staff didnt come in so I was the only one who knew how to develop pictures. Id put all the film into the deep tanks and then heard the noise on the front steps of the rubber sandals of the NVA coming into the office. I thought I must not open the door and wreck history! I put my hands up as I opened the door, and there I found a quite surreal scene. There were two Vietnamese soldiers showing their final route into the city to my bureau chief George Esper and one of our stringers, Ky Nhan Pham. Ky told us: dont worry, these are my friends, so I grabbed my camera and took photos. Forty years on from that defining day, Sarah was one of a group of 40 self-styled Vietnam Old Hacks invited back to Saigon now Ho Chi Minh City by the countrys government. Seeing it is extraordinary, she said. Our AP office is now a very smart shopping mall. I said I have always wanted to meet Ky Nhan Pham again and there he was at one of our dinners. It was amazing to see him.