The United Nations mission in South Sudan says anti-government rebels have opened fire on a peacekeeping base sheltering thousands of civilians, killing at least one person and wounding six others.
The mission, known as UNMISS, released a statement late Wednesday saying the base in the northeastern town of Malakal, which sheltered civilians displaced by the country's violent conflict, was attacked by gunmen on Wednesday. It said U.N. peacekeepers returned fire.
UNMISS said the wounded had been hospitalized and at least one person was in critical condition. It said the attack on civilians and peacekeepers may constitute a war crime, and that it condemns the assault "in the strongest possible terms."
On Wednesday, the United Nations Security Council imposed sanctions on six military commanders from South Sudan for perpetuating the conflict there.
Three government military generals and three rebel commanders are now subject to a global travel ban and an asset freeze.
U.S. Ambassador to the U.N. Samantha Power said the sanctions demonstrate that "those who commit atrocities and undermine peace will face consequences." She said the U.S. and other Security Council members demand both the government and rebels cease offensive military action and commit to negotiating a peace deal.
Fighting in South Sudan erupted in December 2013 between forces loyal to President Salva Kiir and those loyal to former Vice President Reik Machar.
The war has driven more than 2 million people from their homes and created a humanitarian crisis.
The three government commanders sanctioned by the U.N. are Major-General Marial Chanuong Yol Mangok, Lieutenant-General Gabriel Jok Riak and Major-General Santino Deng Wol. The three rebel commanders sanctioned are Major-General Simon Gatwech Dual, Major-General James Koang Chuol and Major-General Peter Gadet.
The U.S. imposed its own sanctions on Chanuong, Deng Wol, Chuol and Gadet last year.
Power said the U.S. is "appalled" by reports of atrocities against South Sudanese civilians, including gang rape and burning people alive in their homes.
It is unclear who is behind such crimes. But U.N. officials have said it is the government's responsibility to protect civilians.