evidence: South Sudan says it was responding to aerial bombardments and a ground attack on its territory, and has shown no desire to pull back. Instead, officials in the capital, Juba, have reiterated a claim that Heglig belongs to the south. [...] Sources say that Khartoum's forces struck first, possibly in an attempt to dislodge South Sudan's army from a base at Teshwin on the disputed border which it had taken two weeks earlier. On Tuesday, the north bombarded several targets in Unity state, in South Sudan, before the ground troops moved in. "The Sudanese attacked first, but they didn't have as many soldiers, so they were forced to flee," said an oil industry worker in the Heglig area who did not want to be named. [...] After Sudan became independent in 1956, disputes and wars over autonomy for the south continued until a peace agreement in 2005. After a referendum, the south declared itself a republic in 2011, and joined the UN and the AU. In July 2009, the permanent court of arbitration redefined the boundaries between north and south, placing the Heglig oilfield in Sudan, but did not specify oil sharing. Based on this, Sudan announced it would not share any of the oil revenue with South Sudan, since Heglig was a part of the north. South Sudan, however, refused to accept the decision saying arbitration court was appointed specifically for the disputed region of Abyei not Heglig.