"We have talked to many [who] had high hopes in Garang, but with his death and the riots that ensued, they seem to be changing their minds about immediate repatriation," Walter Oola, a field manager for the International Rescue Committee, said on Tuesday from Kiryandongo, western Uganda.
Kiryandongo refugee settlement, in Uganda’s western district of Masindi, houses some 15,800 Sudanese refugees.
The spokesperson for the UN Refugee Agency, UNHCR, Roberta Russo, said her agency had planned to start voluntary repatriation by October.
At least 6,000 refugees had been expected to register for repatriation, Russo said, but Garang's death and the riots that followed had "sent some negative signals to the refugee population here".
"Following the death of Garang, this [repatriation of 6,000] may not be achieved," Russo said on Monday from Uganda’s capital, Kampala. "The number may be lower than that."
Oola said many of the refugees who had expressed interest in returning home in a recent survey were now afraid, and were apparently hesitant to be repatriated.
"In a survey of 451 randomly chosen households of about 3,000 people, the youth were reluctant while the elderly wanted to be repatriated later this year," he said.
UNHCR said its plan to begin the voluntary repatriation of refugees to southern Sudan in October, remained on schedule.
According to UNHCR, there were currently over 204,000 Sudanese in camps in western and northwestern Uganda, many of whom had fled the 21-year civil war between the SPLM/A and the Sudanese government.
The war ended when the two parties signed a peace agreement in Kenya on 9 January. Following that agreement, Garang returned to Khartoum and was sworn into office as First Vice President on 9 July.
He was, however, killed in a 30 July helicopter crash near the Uganda-Sudan border as he flew back to southern Sudan following a meeting with Uganda's President Yoweri Museveni.
The Ugandan government-owned MI-72 helicopter came down in bad weather, killing all people on board.
The announcement of his sudden death sparked off a series of bloody riots in the Sudanese capital, Khartoum, and the southern town of Juba, which left more than 130 people dead and many others injured.
Oola added that many of the refugees interviewed had expressed optimism that Garang’s successor as chairman of SPLM/A, Salva Kiir Mayardit, could stabilise the situation.
Other sources said there were also fears that the rebel Lord’s Resistance Army (LRA) could increase its attacks against civilians both in northern Uganda and southern Sudan.
The day before he died, Garang had given the Sudan-based Ugandan rebel group an ultimatum to leave southern Sudan.
"I understand from contacts that the LRA is rejoicing because a key enemy has been removed," John Prendergast, a special advisor to the global think-tank, the International Crisis Group, told IRIN recently. "This could have a serious negative impact for the northern Uganda situation."
The LRA has launched many of its attacks from rear bases in government-controlled areas of southern Sudan. Its leader, the elusive Joseph Kony, is widely believed to inhabit the Imatong mountain range in southern Sudan where the helicopter carrying Garang crashed.
Apart from displacing more than 1.4 million Ugandans, the LRA have on several occasions also launched attacks against Sudanese civilians in the south.
In June, UNHCR reported that since the beggining of 2005, some 9,000 southern Sudanese had fled LRA attacks and sought refuge in northwestern Uganda.
Meanwhile, some 5,000 internally displaced persons (IDPs) who had endured a trek from Western Equatoria State through dense forests and swamps, have returned to western Bahr el Ghazal State, the International Organisation for Migration (IOM) said.
Most of them, IOM added, had arrived at a holding camp in Bile, near the garrison town of Deim Zubeir, while a group of between 500 and 600 people was still en-route to Bile. They would stay at the camp for two months.
According to IOM, it had taken the group more than three-and-a-half months to get to Bile from their camp at Mabia in Western Equatoria, instead of a planned 30 days.
IOM officer Bill Lorenz, who travelled with the IDPs, was quoted by the agency as saying on Tuesday: "They are very happy and relieved they won't have to move for a while. They are also happy to be reunited with their friends and family again after a long time."