HARARE: Zimbabwe President Robert Mugabe sought Thursday to shut down a bubbling succession battle at a key party congress, warning that his embattled deputy and onetime heir apparent could face criminal charges.

The 90-year-old firebrand sought to draw a line under years of unrest within the ruling ZANU-PF, that have seen key lieutenants jockey for position in anticipation that his days in power are coming to an end.

But Mugabe — who has ruled Zimbabwe since its independence in 1980 — is likely to emerge from this week’s congress as the undisputed party leader, the next presidential candidate and with his enemies purged.

On Wednesday, he slapped down speculation he would stand down as “foolish” and idiotic.”

A series of top officials, including former spokesman Rugare Gumbo, have been expelled, but it is Vice President Joice Mujuru who has taken the brunt of the cull.

Seen as a relative moderate, she has endured a sustained campaign led by Mugabe’s wife Grace, who publicly accused her of corruption and even of plotting to assassinate Mugabe.

Last week Mujuru failed to win a seat in ruling party’s central committee, and was not present on Thursday to hear Mugabe describe her as a “thief” and “crook,” while hinting at possible police action.

“As you can see here are gaps here,” Mugabe said referring to Mujuru’s seat.

“Some of our colleagues did not turn up even though we have not chased them away,” Mugabe told some 12,000 delegates gathered at Robert Mugabe Square in central Harare.

He said there had been no explanation for Mujuru’s absence. “That’s the way of crooks.”

“If cases against them are proved, they will be charged,” he said, hinting at a further crackdown.

The congress kicked off after two days of closed door meetings by the party’s top brass.

The conference ends Saturday, with the election of a new leadership. Mugabe is expected to be endorsed unopposed as leader, extending his iron grip on power.

His wife Grace, who made an unexpected entry into politics is likely to be the news women’s league boss.

Grace Mugabe, 49, won a surprise nomination in August to lead the powerful women’s wing of ZANU-PF and has made no secret of her ambition to clinch the southern African country’s top job.

Since her nomination, the former typist has turned political attack dog, leading the campaign against Mujuru.

The party will also approve amendments to its constitution to allow Mugabe to personally appoint his deputies.

The veteran leader who is known for his stinging rhetoric also used the platform to lament division with the party, saying “we have not behaved in a way that shows we are united.”

“Some of us have failed us. Failed you.”

With Mujuru out of the race, eyes have also turned back to 68-year-old Justice Minister Emmerson Mnangagwa.

Long seen a possible successor to Mugabe, Mnangagwa was himself the victim of a purge in 2004 when he lost a key ZANU-PF job after being charged for excessive ambition while angling for the post of vice president which Mujuru then won.

ZANU-PF has been riven by factionalism over Mugabe’s succession for years, with the Zimbabwean strongman avoiding naming a successor.