Three Sudan Red Crescent staff killed in war-torn Blue Nile

South Sudanese refugees cook food at a camp run by the Sudanese Red Crescent on January 27, 2014 in the western part of Sudan's White Nile state (AFP Photo/Ashraf Shazly) (AFP)

Khartoum (AFP) - Three staff of the Sudanese Red Crescent were killed on Sunday in an attack in Blue Nile state, where Khartoum is battling rebels, officials said.

Ahmad Mohammed Adam, a senior official of the Humanitarian Affairs Commission, condemned the attack, which he said "led to the death of three humanitarian workers from the Sudanese Red Crescent Society in Blue Nile state".

The attack happened as the Red Crescent staff were returning from the town of Kurmuk after distributing "humanitarian aid to the needy in the area," he said in a statement.

The statement gave no details about the attack, and a spokesman for the HAC said that it had nothing to add.

The Sudanese military could not be reached for comment and the rebels from the Sudan People's Liberation Movement-North who operate in the region said they did not have any information on the incident.

"I call on the armed movements to respect international humanitarian law and the principle of protecting emergency and aid distribution workers," said Adam.

The town of Kurmuk lies on Sudan's southeastern border with Ethiopia.

The Sudanese government has limited the activities of international relief organisations in areas controlled by the SPLM-N in Blue Nile and South Kordofan states since the insurgency erupted in 2011.