evidence: Heglig, or Panthou (also spelled Heglieg or Pandthow), is a small town at the border between the South Kordofan state of Sudan and the Unity State in South Sudan. The entirety of Heglig is claimed by both Sudan and South Sudan, but administered by Sudan. The area was contested during the Sudanese Civil War. In mid-April 2012, South Sudan's Sudan People's Liberation Army (SPLA) captured the Heglig oil field from Sudan.[1] Sudan took it back at the Second Battle of Heglig ten days later.[2] [...] Heglig is situated within the Muglad Basin, a rift basin which contains much of South Sudan's proven oil reserves. The Heglig oil field was first developed in 1996 by Arakis Energy (now part of Talisman Energy).[citation needed] Today it is operated by the Greater Nile Petroleum Operating Company.[4] Production at Heglig is reported to have peaked in 2006 and is now in decline.[5] The Heglig oil field is connected to Khartoum and Port Sudan via the Greater Nile Oil Pipeline.