The World Food Program reports the Sudanese army Tuesday surrounded two refugee camps near Nyala in southern Darfur province, denying access to humanitarian groups.  

A World Food Program (WFP) spokeswoman, Christiane Berthiaume, says this latest incident is the culmination of tensions, which have been growing in Darfur over the past few days.  She says the events unfolding in Nyala are particularly worrying.

"The army and the police are surrounding the camps since three o'clock this morning [Tuesday morning]," she said.  "They did that without any warning and agencies have been denied access to these camps since this morning.  So, we really do not know what is going on in these camps.  And, our fear is that a relocation operation might start.  But, we do not know.  We have not been to the camps.  And, we have not been allowed to go to the camps."

Ms. Berthiaume told VOA one of the camps, Otash, is home to 17,000 internally displaced people (IDPs).  She says she does not know how many people are living in the other camp Abu Sharif.  But, she says the security forces already have begun moving people out of that camp to another one. 

Sudanese Officials have told UN aid workers local authorities invited them in to remove people from the camp who, they claim, are not true IDPs. but are only there to receive food aid.

Ms. Berthiaume says WFP cannot reach at least 160,000 people with food aid right now, because of the deteriorating security situation.

An estimated 1.5 million people have fled their homes since fighting between two rebel groups and the Sudanese-backed Arab militia, known as the Janjaweed, broke out in February 2003.   

Aid agencies report there has been a marked escalation of violence in Darfur.  While attacks by the Janjaweed militia seem to have eased somewhat, the agencies say there has been a rise in rebel and bandit attacks.  

The UN Refugee Agency says it, along with other international organizations, have had to cancel missions to the field planned for this week.  Spokesman, Ron Redmond, says this follows the kidnapping of 18 Sudanese from a commercial bus on the road between Zalinge and Nyala last Thursday.

"Recently, there have been more reports of rebel activities and that is a concern to us because it also prompts the possibility of retaliatory action by the population against some of the internally displaced people that we are trying to ensure that they can stay where they are at," he said.  "All along, we have been concerned that there could be further displacement to Chad."

Mr. Redmond says he is afraid there might be another mass exodus of people from Darfur to neighboring Chad if international aid agencies are unable to protect the camps.  He notes an estimated 200,000 Sudanese already have fled to Chad.  The influx, he says, is raising tensions between the refugees and local Chadians.