The exact circumstances of the deaths remain under investigation, the authorities have said

South Sudanese soldiers are responsible for killing 16 civilians in Ayod County in Jonglei state, the country's army said on Wednesday. 

Speaking to Eye Radio, South Sudan People's Defence Forces (SSPDF) Spokesperson Major General Lul Ruai Koang promised to punish those responsible. 

"We also regret the loss of life attributed to some elements within the force," Koang said, adding "we do not condone such actions, we took immediate measures: first, the suspects were arrested; second, they will face justice with charges filed against them." 

The SSPDF spokesperson stated the army had detained two unnamed officers and several non-commissioned officers suspected of involvement in the killings. 

The spokesperson explained that their "sentences will be determined based on their level of involvement in the crimes," adding that a general court martial would establish the extent of their guilt. Koang stated that the exact circumstances in which the civilians were killed remain unclear. 

Local authorities in Jonglei state previously reported that 16 civilians were killed on February 21 in Pankor village in Ayod County. Officials said the victims included women and children. 

South Sudan has experienced years of instability since gaining independence from Sudan. 

In January, the UN mission in South Sudan warned of rising violence in Jonglei state.  The mission said the recent hostilities had forced over 180,000 people to flee their homes. It urged all armed groups to return "to consensus-based decision-making" and respect the country's power-sharing arrangements. 

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The violence has also hit other parts of South Sudan. Local officials said at least 169 people were killed when armed youths raided Abiemnhom County in the Ruweng Administrative Area in early March.