South Africa’s High Court ordered former President Jacob Zuma to return to prison on Wednesday, overturning a previous decision to release him on medical parole.

The 79-year-old began medical parole in September and is serving a 15-month term for contempt of court after refusing to cooperate with a corruption investigation.

In the same month, South Africa’s highest court rejected Zuma’s appeal of the punishment.

The court proceedings against him for suspected corruption during his nine-year tenure are widely seen as a litmus test for post-apartheid South Africa’s capacity to uphold the rule of law, particularly against strong and well-connected persons.

Zuma handed himself in on July 7 to begin his prison sentence, triggering the worst violence South Africa had seen in years as his angry supporters took to the streets.

The protests widened into looting and an outpouring of anger over the hardship and inequality that persist in South Africa 27 years after the end of apartheid. More than 300 people were killed and thousands of businesses were pillaged and razed.

Zuma’s legal team are appealing the latest court ruling, his foundation said.

“The judgment is clearly wrong & there are strong prospects that a higher court will come to a totally different conclusion,” the foundation wrote on Twitter.

The Department of Correctional Services said that it was studying the judgment and will make any announcements at a later time.

Zuma’s presidency between 2009-2018 was marred by widespread allegations of graft and wrongdoing, and he faces a separate corruption trial linked to his sacking as deputy president in 2005 when he was implicated in a $2 billion government arms deal.

That trial against Zuma, which has been held up for many years, on multiple charges including corruption, racketeering and money laundering, is expected to continue next year.

He denies wrongdoing in all cases and say he is the victim of a political witchhunt meant to marginalise his faction within the ruling African National Congress. The party said only that it had received the judgment.