South Sudan’s President Salva Kiir has sacked his powerful and long-serving spy chief Gen Akol Koor Kuc.

He became head of the feared National Security Services (NSS) after independence in 2011 and continued throughout the bitter civil war that followed.

No reason was given in the presidential decree that announced his removal, which was read out on national TV on Wednesday night - but he has been made governor of the president’s home state of Warrup, where insecurity is rife.

Analysts say it may signal a power-struggle in Kiir's inner circle - with some believing Gen Kuc may be being lined up to one day take over from the 73-year-old president.

It is not known how old the former spy is - but he is believed to be in his late 50s or early 60s.

The shake-up at the NSS come weeks after it was announced that long-delayed elections, due to take place in December, had been postponed by two years.

While some see Gen Kuc’s appointment to governor as a demotion, others believe the move may also help quell the violence in Warrup State.

It is one of South Sudan’s conflict hotspots, which still sees fighting between rival ethnic communities despite the 2018 peace agreement to end the civil war.

A job as governor would also give Gen Kuc experience in a civilian role, which some believe may be a way of preparing him for political life.

This week has seen violence in Warrup's Tonj North county - with revenge attacks leaving at least 20 civilians dead and 37 others injured, the Netherlands-based Radio Tamazuj quoted the local authorities as saying.

Sources told the BBC that major roads leading to the village of Akok in Tonj North were still blocked by heavily armed young men on Wednesday.

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Gen Kuc’s replacement at the NSS is Gen Akec Tong Aleu - moving from a position in the defence ministry.

Under Gen Kuc’s leadership, the NSS has come in for fierce criticism from human rights groups.

It is known for cracking down on opposition voices - including activists and journalists, with waves of arbitrary arrests and other alleged abusive practices. It denies allegations of abuse.

Oil-rich South Sudan became the world’s newest country 13 years ago after seceding from Sudan - but it was then engulfed by civil war after Kiir and his deputy Riek Machar fell out.

After five years of fighting, they signed a power-sharing agreement, which has been fraught with problems.