A US journalist was Tuesday critically injured by an angry mob as she covered a demonstration against the American arms embargo in Juba.
The demonstrations was organised by various youth groups, including the Sudan People Liberation Movement Youth League.
The incident happened at the UN mission main camp near the Juba International Airport.
The American journalist, who was left unconscious, was rescued by UN peacekeepers and the local police who took her to UNMISS compound for medical attention.
A local journalist who witnessed the incident said the irate youths seemed to be angry at any white person, especially American nationals.
The mob also beat up Julius Gale, a local journalist working for the Juba-based radio Bakhita.
Mr Gale was also covering the demonstration against the US arms embargo.
The South Sudan government was yet to issue a statement on the incident.
The US last Friday announced a ban on arms sale to South Sudan, saying the continuing violence, which has created one of Africa's worst humanitarian crises, showed no signs of ending.
It also said both the government and rebels were heavily spending on military than on peace and development.
Juba reacted angrily to the US action and summoned its ambassador to Washington, Garang Diing Akuong, back home.
Human Rights Watch welcomed the US arms ban, saying it would send a strong signal to the South Sudan leaders that abuses and broken promises would not be tolerated.