Ahmed Hussein Adam, JEM spokesperson, on Wednesday refuted Sudan’s accusations saying senior JEM officials who are fighting against Sudanese army has returned to the field in Darfur since three months ago.

Mohamed Atta Al-Moula, National Intelligence and Security Services (NISS) director demanded Juba administration on Monday to arrest Darfur rebels present in Southern Sudan.

The director also said South Sudan is supporting JEM group, adding Ahmed Adam Bakheit, deputy chairman of the rebel group is in Yei, Central Equatoria while JEM denied their presence in the spot.

The spokesperson has indicated that an accusation about JEM’s presence in Northern Bahr el-ghazal is an attempt to cover up the recent defeats of the Sudanese army in Darfur.

Ahmed said Sudan wants to blackmail the Southern Sudan in the negotiations on the referendum, and to mask Khartoum’s support to the Lord Resistance Army.

Sudan presidential adviser, Abdalla Massar, renewed the allegations relating South Sudan’s harbour JEM rebels in the South to use them in a probable conflict against the central government as the referendum would not be run as scheduled next January.

Southern Sudan authorities have already accused Khartoum of supporting General Athor who mutinied in Jonglei sate after April elections.

Southern Sudan government had seized a helicopter on August 8 in Fulug county airport in the Upper Nile State and accused the Sudanese army of shipping weapons and ammunition to the rebel general to derail the referendum process.

Sudan has recently accused Uganda of supporting JEM rebels who clashed last week with the Sudanese army in different parts of Darfur and Kordofan.

Tensions between North and South Sudan border region of Abyei might be the cause of a new regional conflict that would destabilize the whole region.

Leaders in North Sudan have said it is now impossible to hold a referendum on the future of an oil-rich region along the country's north-south border while southern Sudanese politicians have insisted that the vote must go ahead.

The vote on Abyei region is scheduled to take place at the same time as the referendum on southern independence. Abyei residents would decide whether to remain in the north or join the south.

It was part of the 2005 deal that had ended Africa’s longest civil war that killed about two million people and displaced another four million.