Willie Amutenya leading children in a dance. Willie Amutenya was captured at the Vietnam Camp, 50 km from the Namibian border, on the same day as the Cassinga attack in 1978 and held for years at Keikanachab prison, Mariental. The Battle of Cassinga, Cassinga Raid or Kassinga Massacre was a controversial South African airborne attack on a SWAPO refugee camp and military base at the former town of Cassinga, Angola on 4 May 1978.