Russian contractor Safinat is evacuating all staff from its South Sudan Unity oilfield after five men were injured in crossfire between the government and rebels.
The company is arranging to fly the injured workers from a UN base in the Unity state to the capital Juba.
Rebel leader Riek Machar claimed this week to have captured the capital, Bentiu.
The claim was denied by the ruling Salva Kiir administration.
Gunfights have continued in the disputed area around the oil fields.
According to sources, a fire fight between rebels and the Sudan People’s Liberation Army (SPLA) erupted near Safinat’s camp at Unity oilfield.
One of the wounded, a Kenyan national, remains in a serious but stable condition.