South Sudanese leader Salva Kiir has fired one of his vice-presidents, Benjamin Bol Meir, who had been considered a possible successor to South Sudan.

Kiir stripped Bol Meir of his general rank and relieved him of his national security duties. He also fired the central bank governor and the head of the tax agency, both considered close allies of Bor Meir.

The dismissal was announced in a decree broadcast on state television without any explanation for the dismissal.

There are growing concerns about political instability and a possible return to civil war after the recent collapse of a fragile power-sharing deal between Kiir and opposition leader Riek Machar.

Bol Mel, 47, was appointed vice president in February, replacing veteran politician and general James Wani Igga.

He was also promoted to first vice-president of the ruling Sudan People’s Liberation Movement, which analysts believe gives him more power and makes him a potential candidate The successor of 74-year-old Kiir. The president later promoted him to National Security Service (NSS) general.

Bormeir’s appointment comes despite U.S. sanctions imposed on him in 2017 over alleged corruption and extended earlier this year. The U.S. Treasury Department described Bormeier as Kiir’s “chief financial adviser.” Kiir’s office denied that characterization.

He has never directly responded to the corruption allegations against him, nor has he commented on his dismissal.

The president has not yet announced a replacement for any of the positions he holds.

He was dismissed following speculation on social media about a power struggle within the Sudan People’s Liberation Movement.

A government source, who spoke on condition of anonymity for security reasons, told the BBC that Bormeier had been a “divisive figure” in the government.

“It’s great that he’s gone,” he said.

South Sudan is an oil-rich country that became the world’s newest country after breaking away from Sudan in 2011. Two years later, the country descended into civil war after Kiir and Machar fell out.

The power-sharing deal that ended the war in 2018 has been fraught with challenges, with tensions lingering and sporadic violence continuing to break out.

Planned elections have been postponed twice in the past three years and fighting between forces loyal to the president and armed groups has recently escalated.

Machar was sacked as vice president and arrested earlier this year and charged in September with murder, treason and crimes against humanity, a move seen as escalating tensions and raising fears of a new wave of civil unrest. The case is ongoing.

His spokesman described the accusations against him as a “witch hunt.”

The charges followed an attack by militias allegedly linked to Machar that the government said killed 250 soldiers and a general.