UN Secretary-General Ban Ki-moon on Tuesday condemned the killing of peacekeepers in an ambush in the east part of South Sudan, saying he was "appalled" by the incident.
Ban was "appalled by the attack on an UNMISS (UN Mission in South Sudan) convoy this morning," said a statement issued here by Ban's spokesperson.
"He condemns in the strongest terms the killing of five Indian peacekeepers and two UNMISS national staff and five civilian staff contractors in Gumuruk, Jonglei state, South Sudan," said the statement.
The UN mission in South Sudan said in an earlier statement that a number of its peacekeepers and some civilians were killed on Tuesday in an ambush staged by unknown militants in the country's east.
However, the statement did not specify the exact number of casualties or their nationalities in the attack that occurred in Jonglei state.
Jonglei, the largest state in the eastern part of South Sudan, has been the scene of inter-communal violence since the African country won its independence.
According to Ban's statement, nine other UNMISS staff were also injured in the attack, some in critical condition. In his statement, the UN chief called on the government of South Sudan to bring the perpetrators to justice, saying the killing is a "war crime."
"The secretary-general expresses his deepest condolences to the governments of India and South Sudan and to the families of the peacekeepers, staff members and contractors killed in the attack," the statement added.
UNMISS said later that the attack represented the highest single loss of life since an increase in inter-communal violence began several months ago.
The UN mission has been in South Sudan since 2011 to help the government restore security to the newly created country where a huge amount of weapons are in the hands of fighters.