South Africa's ruling ANC begins fight to replace under-fire leader Jacob Zuma
The fight to replace South Africa's scandal-prone president has started as thousands of delegates of the ruling African National Congress gathered to elect a new leader.
The reputation of Nelson Mandela's liberation movement has been battered during the tenure of Jacob Zuma, whose second term as party president is up.
The two clear front-runners are deputy president Cyril Ramaphosa and Nkosazana Dlamini-Zuma, former chairwoman of the African Union Commission and Mr Zuma's ex-wife.
Voters are frustrated with the ANC as Mr Zuma's administration has been mired in scandal and corruption allegations.
Africa's oldest liberation movement, which celebrated its 105th anniversary this year, led the fight against white minority rule and has governed South Africa since the first democratic elections in 1994.
Observers say the party needs to restore its reputation or it could be forced into a governing coalition for the first time.
Party divisions run so deep that analysts say either outcome, Mr Ramaphosa or Ms Dlamini-Zuma, could mean the end of the ANC's dominance as members of the losing faction could form a new party.
"We must attend to enormous challenges facing our movement," Mr Zuma told the gathering, which opened with emotional appeals for unity.
He pushed back against allegations of graft, asserting that "theft and corruption" in the private sector is just as bad as in government and that "being black and successful is being made synonymous to being corrupt".
Mr Zuma also said "greed is posing a serious threat" to the party and warned that the ANC could "implode".
He also rejected the party's "petty squabbles" that have distracted the ANC from its work and said challenges to inclusion are "killing our movement".
The president defended the party's worth despite the challenges, saying it continues to stand for millions of people on the fringes of society.
"A heavy responsibility lies upon the shoulders of delegates here ... to renew our movement and to restore its timeless values," he said.
He lashed out at the media, the judiciary and civil society, accusing them of fighting the ANC or interfering in party matters.
He could carry on as head of state until 2019, when his term ends, or he could step down or be ousted before then by the new party leader ahead of the general elections.
Under Mr Zuma, unemployment has risen to nearly 30% and economic growth has slumped. More than 55% of the country lives below the poverty line.
Mr Ramaphosa, who helped negotiate an end to apartheid and has become one of the wealthiest men in a democratic South Africa, has pledged to crack down on corruption and get the economy back on track.
Ms Dlamini-Zuma, a doctor and former government minister and an ally of the president, has promised to bring more black South Africans into the fold through "radical economic transformation".
Some South Africans worry that she would be influenced by her ex-husband and perhaps shelter him from prosecution.
The growing frustration around Mr Zuma led the party to suffer its worst-ever performance in municipal elections in 2016, with its vote share falling below 60% for the first time.