The US lost thousands of aircrafts in the course of the Vietnam War. The surviving crews of those planes downed over North Vietnam were inevitably captured by the Vietnamese forces. For some time, they were held close to the border regions. However, after the US launched Operation Ivory Coast, the failed rescue operation of POWs in the North, the Vietnamese moved the American POWs into the cities. The most famous prison was Hoa Lo, known in the West as Hanoi Hilton. Senator John McCain was once held there went he was shot down over North Vietnam. The government of the North used the POWs for propaganda, showing various footages of their lives in order to sway the American public opinion. For example, one of the most famous episode was the footage of the Christmas celebration organized for the American captives.