Zambia’s former President Edgar Lungu has died at the age of 68, his party has said in a statement.

He had “been receiving specialized treatment in South Africa” for an undisclosed illness, the Patriotic Front (PF) added.

Lungu led Zambia for six years from 2015, losing the 2021 election to the current President Hakainde Hichilema by a large margin.

In a short video, Lungu’s daughter Tasila said that the former head of state, who had been “under medical supervision in recent weeks”, died at a clinic in South Africa’s capital, Pretoria, at 06:00 (04:00 GMT) on Thursday.

“In this moment of grief, we invoke the spirit of ‘One Zambia, One Nation’ – the timeless creed that guided President Lungu’s service to our country,” she added in an emotional statement.

There was no mention of what his condition was, but a decade ago he underwent throat surgery abroad. At the time his office said he was suffering from a narrowing of the oesophagus.

In his condolence message, President Hichilema called for “solemnity, unity and an outpouring of love and compassion.

“Let us come together as one people, above political affiliation or personal conviction, to honour the life of a man who once held the highest office in our land.”

Cyril Ramaphosa, the president of South Africa, where Lungu was being treated, wrote that it was a “privilege in recent weeks to care for a leader from our region whom we embraced as a brother and friend. We therefore share the grief and loss experienced.”

Lungu first became president in January 2015 after winning a special presidential election triggered by the death in office of Michael Sata.

After completing Sata’s term, he won a further five years in power in 2016 taking just over 50% of the vote.

But after six years at the helm, Lungu was blamed for a struggling economy, high unemployment and rising debt levels.

His time in office was also marred by corruption scandals involving his allies and relatives. Lungu always denied wrongdoing.

His party’s youth wing was accused of harassing opposition supporters, and the population at large.

Lungu lost in 2021 by close to a million votes with Hichilema, seen as more pro-Western, tapping into widespread dissatisfaction among the electorate.

He said he was retiring in the aftermath of the vote, but returned to frontline politics in 2023 as his successor’s popularity waned.

“I am ready to fight from the front, not from the rear, in defence of democracy. Those who are ready for this fight, please come along with me, I am ready for anything,” Mr Lungu told supporters at the time.

After returning to politics, the former president complained of police harassment. At one point last year he said he was “virtually under house arrest”.

“I cannot move out of my house without being accosted and challenged by the police and driving me back home”, Lungu told the BBC’s Newsday programme.

Lungu was a lawyer by training but enjoyed a meteoric rise in politics after winning a seat in parliament as a PF MP in 2011.

He entered government as deputy minister in the vice-president’s office in that year and rose to become minister of home affairs in just over 12 months.

He later became minister of defence and then justice. A close friend described Lungu as a “good foot-soldier, lawyer and politician, father, husband and grandparent”.

Born on 11 November 1956, Lungu graduated with a law degree from the University of Zambia in 1981. He also underwent military training at the then Miltez army college in Kabwe.