US Journalist Christopher Allen is seen with SPLA-IO forces at the border with Uganda before the fateful attack on Kaya town, where he was killed in Yei River State | File photo

UN human rights expert has denounced lack of investigation into the killing of foreign journalist in South Sudan three years ago.

A dual British-American citizen, Christopher Allen was killed in South Sudan on August 26, 2017, while he was covering clashes between opposition and government troops in the town of Kaya.

Allen had been reportedly embedded with the opposition forces in there for a week before he was killed.

Images of his body, stripped naked, were widely shared online.

Since then, no one has been held accountable for the killing of Allen.

However, senior South Sudanese Government officials reportedly “justified” the killing, labelling him a rebel and a criminal who entered the nation illegally.

UN Special Rapporteur on extrajudicial, summary or arbitrary executions, argues that the absence of a proper investigation sends a “very dangerous signal” that journalists and media workers can be targeted with impunity.

“Three years is too long to leave a bereaved family without answers,” says Agnès Callamard in a news release issued on Tuesday.

More than 10 other journalists were killed during the civil war in South Sudan, but without accountability for the crimes.

“Investigation into crimes committed against journalists – not only in South Sudan, but around the world – is a key element in preventing future attacks and ending impunity,” she added.