This photo taken November 8, 2017, shows Zimbabwe's President Robert Mugabe, left, addressing party members and supporters to show support to Grace Mugabe, right, becoming the party's next vice president after the dismissal of Emerson Mnangagwa.
The ZANU-PF party criticised General Constantino Chiwenga who had demanded that Mugabe stop purges of senior party figures, including Vice president Emmerson Mnangagwa who was dismissed last week.
Zimbabwe's top military commander on Monday urged the ruling Zanu-PF party to put its house in order, saying the military would step in if the revolution that brought independence was under threat.
In a statement, the party spokesman said Chiwenga's stance was "clearly calculated to disturb national peace... and suggests treasonable conduct on his part as this was meant to incite insurrection".
Although the ruling ZANU-PF party has said it would never succumb to military pressure.
"I saw a long convoy of military vehicles", a female fruit seller about 10 kilometres (six miles) from central Harare, told AFP, while other witnesses took to social media to confirm the reports.
Several military tanks and trucks were spotted heading towards the Zimbabwean capital Harare Tuesday, prompting fears of a possible coup or show of power by the army.
Mnangagwa, 75, was widely viewed as Mugabe's most loyal lieutenant, having worked alongside him for decades.
Earlier this year the country was gripped by a freaky spat between Grace and Mnangagwa that included an alleged ice-cream poisoning incident that laid bare the pair's rivalry.
"We will not fold out hands to allow a creature of the constitution to subvert the very constitution which establishes it", said Kudzai Chipanga, who leads the Zanu-PF Youth League, said at the party's headquarters in Harare.
President Robert Mugabe with his wife Grace Mugabe.
Mugabe has broken with most of his allies who fought in the liberation war against the white-minority regime of Rhodesia, leaving the so-called Generation-40 faction of younger members of the ruling party championed by his wife, Grace Mugabe, 52, in the ascendancy.