South Sudan’s armed forces have admitted to shooting down a United Nations helicopter killing all four crew members, earlier on Friday.

South Sudanese army spokesperson Philip Aguer stated that one of their artillery units had spotted the aircraft, suspecting that it would  resupply rebels led by David Yau Yau. Aguer said,

"We regret the incident,"

"The artillery unit unfortunately fired on the plane [believing] that this is an enemy plane because there was no prior information from the UN about this plane being in the area,"

"We saw a white plane landing and asked UNMISS whether they had any flight in the area but they denied it. The army opened fire because it thought it was an enemy plane supplying Yau Yau with weapons."

"We later heard UNMISS had a flight there. They should have informed us."

A spokesman for UN Secretary General Ban Ki Moon said,

"The secretary-general strongly condemns the shooting down today of a clearly marked UN helicopter by the Sudan People's Liberation Army near Likuangole, in Jonglei State of South Sudan."

He further went on to call on South Sudan to "immediately carry out an investigation and bring to account those responsible for this act".

The UN Security Council also said it "strongly deplores" the "grave violation" of UN accords, and the US State Department also said that it "deplores" the attack, with both calliong for a full investigation.