A South Sudanese man working for aid organisation Joint Aid Management (JAM) was shot dead in the country's north, an association of humanitarian groups said Tuesday.

The man "was shot dead by unidentified persons whilst returning from humanitarian operations supporting vulnerable families" near the city of Bentiu on January 30, the South Sudan NGO Forum said in a statement.

"One additional humanitarian staff member from JAM was also injured in the attack and has been receiving treatment".

The NGO Forum said members were "horrified by attacks on aid workers," with the latest coming as groups "scale up response to food insecurity, flooding, local violence and the Covid-19 pandemic".

South African organisation JAM says on its website that it has been running food aid schemes in South Sudan since 2001.

In its statement, the Forum highlighted that "2020 saw a significant rise in the number of aid workers killed or harmed in South Sudan, a trend that must not be allowed to continue in 2021".

Two humanitarian workers were killed in the same week in eastern state Jonglei in early November.

The same month, the UN Office for the Coordination of Humanitarian Affairs said nine aid workers had been killed over the course of the year -- triple the toll in 2019.

In recent years, South Sudan has become one of the most dangerous places worldwide for aid workers, with increasing numbers of attacks on individuals and their organisations' convoys across the country.

The country is struggling to emerge from a six-year civil war that claimed some 380,000 lives and officially ended with the creation of a government of national unity in February last year.

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