JUBA, 14 June 2011 (IRIN) - Aerial bombardments, killings of civilians and house-to-house searches are escalating in the Northern Sudanese state of Southern Kordofan, aid workers and residents report.

The UN Office for the Coordination of Humanitarian Affairs (OCHA) estimates that some 53,000 people have been displaced by fighting that broke out on 5 June near Kadugli, the state capital, between the Northern army, the Sudan Armed Forces (SAF), and former members of the Sudan People's Liberation Army (SPLA).

The ex-rebel SPLA is now the official army of the South, which is due to become fully independent on 9 July, after voting overwhelmingly to separate from the North in a January referendum.

But many from Southern Kordofan fought for the SPLA, especially in the central Nuba Mountains, which was one of the hardest hit and most bitterly fought over areas of all of Sudan's two-decades-long civil war.

Now they find themselves on the wrong side of the border from former comrades as the South prepares to separate, and have resisted surrendering weapons to forces they see as hostile.

Those tensions exploded with deadly consequences last week.

On 14 June, artillery shelling was reported near Kadugli town, while two SAF planes bombed the airstrip at Kauda, said Hua Jiang, spokeswoman for the UN Mission in Sudan (UNMIS), the latest in a series of aerial attacks.

"This is like the worst days of the last war," said one aid worker in the state, who could not be named for security reasons.

"There are horrific killings but it seems like they are just being ignored," he added.

While officials in Khartoum insisted only rebels were being targeted, sources in Kadugli told IRIN people in the streets had been killed for looking "too black", and with no regard for whether or not they supported the SPLA.

In ethnic terms, the people of the Nuba Mountains usually identify more closely with the "African" Southerners than the Northern Arab majority.

Rights groups condemn attacks

"Amnesty International has received reports from residents of the besieged towns of Kadugli and Dilling that the SAF, as well as Sudanese security forces in plain clothes, have been searching streets and houses, arresting and killing people suspected of supporting the SPLA," it said in a 10 June statement.

Inside the Nuba Mountains region of Southern Kordofan, where heavy and repeated aerial bombardments have been reported, people are digging makeshift air-raid shelters in riverbeds.

Children have been moved into caves in the hills for shelter, while their parents try to move their few remaining stocks of food to safety, sources in the area reported.

"Looting and destruction of property have been widespread," Amnesty added. "Civilian homes and NGO offices have been raided."

Although numbers of reported casualties remain low, aid workers warn that that is because they are based largely on the number of those taken to hospitals, and because aid agencies and UNMIS cannot yet verify totals elsewhere.

"As the majority of fatalities are probably not taken to hospital, the real death toll is undoubtedly higher - and likely much, much higher," said one international aid worker, basing his assessment on "multiple" on-the-ground reports.

UNMIS has been criticized over its alleged failure to protect civilians.

"Reports from the ground indicate that military personnel arrested people who had sought refuge inside the UNMIS compound, in violation of international humanitarian law," Human Rights Watch (HRW) said in a 10 June statement.

"One of those arrested was later found dead," it added.

The Sudan Democracy First Group, a coalition of civil society activists, released a 13 June report listing some of the names of those they allege have been killed by government forces, including Sudanese employees of UNMIS.

At least two were killed outside the UN compound walls, the group said.

"We are in the process of investigating these allegations, and are taking them very seriously," said Hua Jiang, adding that some non-essential staff had been relocated from Kadugli to El Obeid, in Northern Kordofan State.

"It is a difficult situation there, and both military and civilian components are doing all they can," she added.

Bombing raids have also spilled across the Southern border into Unity State, officials there say, infuriating the South.

Meanwhile, newly elected state governor Ahmed Haroun, a key member of Khartoum's ruling National Congress Party (NCP) and wanted by the International Criminal Court (ICC) on war crimes charges in Darfur, has vowed to track down the state's former deputy governor Abdel Aziz Al-Hilu, a top SPLM official.

"He (Al-Hilu) is personally wanted for justice since he has caused the death of many citizens," Haroun said, according to the Sudan Media Centre, a website close to Northern security forces.

"The armed forces and other regular forces are exerting extensive efforts to arrest him," he added.

Food security fears

Fighting also has a long-term impact, aid workers warn, noting that it will impact agricultural production, with the harvest period due in a few months time.

"From now on, this is when people's food supply is typically scarce and stocks will quickly start to run down," an aid worker in the Nuba Mountains said.

"If the war spreads as predicted, you can imagine the humanitarian catastrophe it will create."

On 14 June, the UN Refugee Agency (UNHCR) called on Khartoum and authorities in Kadugli to allow air and road access to the area.

"For nearly one week now, humanitarian flights have been denied authorization to land in Kadugli despite our efforts to secure such an agreement. Land access is also being hampered by armed militiamen who have set up roadblocks, from which we are hearing reports of harassment of people on the move," the agency stated.

"Insecurity means our operations are severely constrained and UNHCR is currently unable to reach a warehouse just 5km from the UN peacekeeping mission's base in the city. The warehouse contains supplies to assist 10,000 displaced people."

Source: The Integrated Regional Information Networks (http://www.irinnews.org )