Security forces on Wednesday searched houses for illegal weapons in a disarmament drive in Sudan's southern regional capital, where US envoy Scott Gration met officials to help bolster a fragile peace deal.
Gration began two days of talks with officials from both the National Congress Party that leads the Khartoum government and the south's dominant Sudan People's Liberation Movement (SPLM) to seek progress on the 2005 Comprehensive Peace Agreement (CPA) that ended their 22-year long civil war.
"We will concentrate on finding a path forward on the two remaining unresolved sticking points for full CPA implementation," Gration said in a statement.
Key issues include disputed census results and the framework of a promised 2011 referendum on independence for the south.
"These are fundamental issues that must be resolved soon," Gration said.
A US-based pressure group urged the envoy to take a harder line with the NCP -- the party of President Omar al-Beshir, accused by the International Criminal Court (ICC) of crimes against humanity in the troubled western Darfur region.
"Left unchecked, the NCP?s behaviour will trigger a war in the south and make it all the more difficult to resolve the still-simmering crisis in Darfur," the Sudan Now advocacy umbrella group warned in a letter.
"The current US diplomatic strategy is making peace more difficult by opening the door to a renegotiation of key aspects of the CPA?s implementation," it added.
The US envoy's visit came as security forces carried out a major operation in Juba to seize illegally held weapons.
Security forces blocked roads at dawn as police and soldiers searched house to house and UN staff were ordered to remain at home.
"It is a disarmament effort to take illegally held guns from the people," said Major General Kuol Diem Kuol, of the SPLM's military wing, the Sudan People?s Liberation Army. "The SPLA is supporting the police who are the forces leading this action."
By 1 pm (1000 GMT) roads began to reopen, although security forces continued to check vehicles and search for arms at checkpoints across the city.
It was not immediately clear if the disarmament drive was limited to Juba, or if it would be rolled out to other areas.
"This is an ongoing operation run by the ministry of the interior," said Kuol.
"It is aimed at improving people's security and safety by removing these dangerous weapons from civilian hands."
Security forces have launched several previous attempts to seize arms across the south, a region awash with automatic weapons left over from Africa's longest-running civil war.
However, previous disarmament campaigns have been criticised for exacerbating violence. Heavy-handed but ineffective, they have left some regions at risk of attack from their still armed neighbours.
More than 2,000 people have died and 250,000 been displaced in inter-ethnic violence across south Sudan since January, according to the United Nations, which says the rate of violent deaths now surpasses that in Darfur.
