Zimbabwe is on edge amid speculation that a military coup is in progress, with army tanks seen outside the capital a day after the army commander threatened to "step in" to calm political tensions over the president's firing of his vice president. The Associated Press said it saw three tanks with several soldiers in a convoy on a road heading toward an army barracks just outside the capital, Harare, while Reuters reported that four tanks were seen heading toward the capital.

According to Reuters, two other tanks were seen parked beside the main road from Harare to Chinhoyi, about 20km from the city. Eyewitnesses also saw military vehicles blocking major roads outside the city.

BREAKING: Tanks and military vehicles are blocking the roads leading to Zimbabwe capital of Harare, reports of a possible standoff between the army and President Mugabe pic.twitter.com/7sX3ZsOD0Q

— News_Executive (@News_Executive) November 14, 2017

The alleged coup takes place one day after Zimbabwe's army chief demanded a "stop" to the purge in President Robert Mugabe's ruling Zanu-PF, following the sacking of vice president Emmerson Mnangagwa. Mnangagwa was well-supported by the Zimbabwean national forces. On Monday, Amry General Constantino Chiwenga told a media conference attended by at least 90 senior army officers at the army headquarters in Harare on Monday that: "The current purging which is clearly targeting members of the party with a liberation background must stop forthwith."

According to New Zimbabwe.com, Chiwenga recently returned from a trip in China to find Mnangagwa fired from government and expelled from Zanu-PF. The report said that the army had been seen to be backing Mnangagwa to succeed Mugabe, 93, but the nonagenarian's wife Grace had emerged as a top contender. Mnangagwa was kicked out of both government and the ruling party last week following accusations that he was plotting to topple Mugabe from power. 

This prompted the army chief to accuse Zimbabwe's ruling party of expelling senior officials who participated in the 1970s war against white-minority ruled Rhodesia, saying "counter revolutionaries" were plotting to destroy the party. This was the first time Zimbabwe's military directly criticised the infighting in Zanu-PF and marked a rift between Mugabe and an institution that has been a key pillar of his power.

"The current purging and cleansing process in Zanu-PF which so far is targeting mostly members associated with our liberation history is a serious cause for concern for us in the defense forces," said Chiwenga, at a press conference, reading from his statement.

He then warned those "behind the current treacherous shenanigans that when it comes to matters of protecting our revolution, the military will not hesitate to step in. The current purging of which is clearly targeting members of the party with a liberation background must stop forthwith."

It appears that one day later, Chiwengae has made good on his threat, with tanks deployed around the capital. Local media also reported that heavily armed military personnel had sealed off state TV broadcaster ZBC.

#Zimbabwe We might see the fall of the old men #RobertMugabe pic.twitter.com/foaSF3lZ4K

— NAZEEM GROOTBOOM (@Unathi_007) November 14, 2017

As AP adds, while it is routine for tanks to move along that route, Tuesday's timing heightens unease in this country that for the first time is seeing an open rift between the military and 93 -year-old President Robert Mugabe.

Meanwhile, reports on the ground from Zimbabwe suggest that a coup may indeed be taking place. A flurry of photos – shared by journalists across Twitter – show a fleet of the armoured vehicles making their way to the country’s capital.  The convoy has taken to the streets just a day after the head of the armed forces said he was prepared to “step in” to end a purge of supporters of ousted vice-president Emmerson Mnangagwa.

It seems like finally Zimbabwe's military is beginning to have some sense,something that should have perhaps happened 20yrs ago.The culture of allowing leaders to turn countries into personal property should never be tolerated!!

— Cappy Gerald ™ (@CappyGerald) November 14, 2017

Tank movement in #harare #zimbabwe pic.twitter.com/SMZA34eU60

— IamDumbToo (@IamDumbToo) November 14, 2017

A journalist in Harare has told News24 that "it seems the army is angry". He says the situation is a bit "tense" in the capital.

Zimbabwe: Army chief calls for end to #Zanu-PF purges By SALLY NYAKANYANGA pic.twitter.com/0EkhF4hE29

— Francisco A.González (@FcoAGonzalez) November 14, 2017

Some on Twitter are saying that although a coup is almost never a good thing, it brings an end to Mugabe's much despised regime.

Meanwhile, in a sign that events may turn violent, earlier on Tuesday, The Zimbabwean reported that Zimbabwe’s Zanu-PF youths said they were “prepared to die” in defence of President Mugabe’s government. In a statement on Tuesday, Zanu-PF’s secretary of the youth league Kudzai Chipanga said that Zanu-PF youths did not take lightly the military’s threats.

“We as Zanu-PF youth league are a lion which has awakened and found its voice, therefore we will not sit idly and fold our hands whilst cheap potshots and threats are made against Mugabe,” Chipanga said.

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Here is Al Jazeera with a brief explainer of the political crisis in Zimbabwe that threatens to sweep Robert Mugabe from his post:

Zimbabwe is facing a political crisis with the ruling Zanu-PF party, as a very public showdown over who is likely to succeed President Robert Mugabe plays out. The current standoff is between the Youth faction, loyal to his wife, Grace Mugabe, and the former liberation fighters, loyal to Emmerson Mnangagwa, the vice president who was fired last week. Al Jazeera's Hannah Hoexter explains.

Readers can track live updates from the alleged coup at the following live feed.