South Sudanese army Friday said it has lost contact with its troops in Malakal, the capital city of the oil-rich Upper Nile State which has been witnessing clashes between the government forces and rebels since last month.
"We have lost contact with our forces in Malakal," Xinhua quoted Philip Aguer, a spokesperson of the South Sudanese army, as saying.
"Our forces are still in Malakal and we are still trying to contact them," Aguer added, without giving any further details.
Since mid December, South Sudan has been witnessing violent clashes between government troops and forces loyal to former vice president Riek Machar, who is accused of plotting to topple the government.
The clashes have left some 1,000 people dead, over 400,000 civilians displaced, and forced some 63,000 others to take refuge at various UN compounds around the country, according to UN reports.