Fighting continued between Sudan and South Sudan in the oil rich Heglig border area Wednesday, with Sudanese troops beaten back by the forces of its newly independent southern neighbor.

After two days of fighting, reports indicated the South Sudanese army (SPLA) has seized control of the Heglig oil fields, a vital strategic resource for Khartoum which accounts for over half of Sudan's domestic oil production.

Since South Sudan seceded in July, both countries have been locked in a battle for control of the ill-defined border areas.

Ongoing skirmishes between the pair have raised concerns that fighting might escalate into full-blown war.

According to an SPLA spokesman, South Sudanese troops were attacked by Sudanese troops on Monday in the town of Teshwin.

After repulsing the attack, SPLA troops then pursued Sudanese troops across the border into Heglig.

They launched a new attack, and occupied southern territory until the SPLA repulsed them, said Philip Aguer, a spokesman for the South's forces, according to Reuters.

We repulsed and pursued the SAF (Sudanese Armed Forces) up to Heglig.

While reports indicated SPLA forces were now in control of Heglig, Aguer refused to confirm or deny the reports, adding that he had difficulty communicating with forces on the ground.

A statement released by the Sudanese Media Centre on Tuesday said Sudanese troops were battling South Sudan's aggression ... on our southern border in the direction of Heglig.