By Hereward Holland
JUBA, Dec 13 (Reuters) - The United Nations will investigate the deaths of at least nine civilians shot by South Sudanese security forces last weekend in the country's northwest.
South Sudan's government has been struggling to reform its bloated security services since it split from Sudan in July last year after a long civil war that has left the new country awash with weapons.
Human rights groups regularly accuse South Sudan's army, an assortment of poorly-trained former guerrilla fighters known as the SPLA, of abuses against civilians.
About 2,400 people have been killed in rebel and tribal violence since independence, the United Nations says.
The SPLA said police and soldiers had opened fire on civilians last weekend who were protesting against the relocation of local council offices.
South Sudan's Civil Society Alliance, an umbrella group for local civil society organisations, quoted witnesses saying the demonstrators had been unarmed and protesting peacefully.
"UNMISS (the U.N. mission in South Sudan) is investigating the use of force and other reports of violence in order to establish the facts behind these tragic events," UNMISS said in a statement.
"Nine civilians have been confirmed killed and many more injured in incidents involving demonstrators and members of the security forces," UNMISS said.
The violence in Western Bahr el Ghazal state's capital Wau began on Dec. 8 when the army was sent to dismantle road blocks set up by civilians protesting against plans to move the municipal council headquarters outside Wau.
The following day, security forces fired on protesters marching towards state government offices with a petition asking the governor to reverse the decision. SPLA spokesman Kella Kueth said the protesters burnt nine trucks.
"They were thought to be destroying the government property and that is when they were fired upon by police and some army forces," Kueth told Reuters.
Ateny Wek, spokesman for the Civil Society Alliance, said two more people had died from their injuries, bringing the death toll to eleven, with scores of others injured.
"It was barbaric for the state authorities to use live ammunition. They were marching peacefully towards state government headquarters. We have eyewitnesses," Wek told Reuters. (Editing by Jane Merriman)