Mugabe and his wife, Grace, with VP Emmerson Mnangagwa

Zimbabwean police on Thursday fired teargas and water cannon to disperse hundreds of war veterans planning a march on the ruling party’s headquarters, witnesses said, as factions tussle over who should succeed President Robert Mugabe.

War veterans have previously mobilised election support for Mugabe, a fellow veteran who turns 92 on Sunday, but they have publicly criticised a group in the ruling ZANU-PF party led by Mugabe’s wife Grace which has been dubbed G-40 by local media.

Though Grace Mugabe has said she has no ambitions to run for president, experts believe she is a leading candidate to succeed her husband, with Vice President Emmerson Mnangagwa also a likely frontrunner and part of a rival Zanu-PF faction.

Witnesses saw police fire teargas and chase war veterans from a sports centre outside Harare’s central business district, breaking them into small groups at a nearby open ground.

A Reuters photographer later saw police spraying the groups with water cannon. Dozens of armed police kept watch at the ZANU-PF offices.

The veterans who fought in the war that led to independence from Britain in 1980 have been angered by what they call disrespectful comments by Grace Mugabe and her G-40 allies.

They say she and her allies do not have support within the ruling party but are using their proximity to Mugabe to manipulate him.

However, for all the talk of succession, Mugabe shows no intention of stepping down, despite being Africa’s oldest leader and the only president Zimbabwe has known since independence.

The G-40 has attempted to fire some leaders in the Zimbabwe National Liberation War Veterans Association (ZNLWVA). In turn, the ZNLWVA has affirmed support for its leaders and branded the G-40 group “counter-revolutionaries”.

ZNLWVA secretary general Victor Matemadanda said the organisation would hold a news conference later on Thursday.

The G-40 group accuses veterans of trying to force Mugabe to retire in favour of Mnangagwa, nicknamed “Crocodile”, which he says reflects his ability to strike at the opportune time.

War veterans deny the charge but favour one of their own to succeed Mugabe. Mnangagwa, like Mugabe, is a veteran.

Grace Mugabe did not fight in the independence war but hinted last week Mnangagwa may not be Mugabe’s chosen heir and condemned veterans for arrogance.