He said the events in the capital tonight were not part of "a military takeover of government" and President Robert Mugabe was safe.
Soldiers quickly seized the state broadcaster, ZBC, manhandled its staff and read out a statement announcing its plans, Reuters reported.
The military added that Mugabe and his family were "safe and sound and their security is guaranteed".
"We are only targeting criminals around who him who are committing crimes that are causing social and economic suffering in the country in order to bring them to justice".
According to the army general, they expect that the situation will return to normalcy "as soon as we have accomplished our mission".
Mr. Chombo is a prominent member of a faction of the ZANU-PF party supporting Mr. Mugabe's wife, Grace's bid to succeed her husband.
"But now‚ this caging that is happening‚ could maybe sway the army generals to say that Mugabe never went on the ground‚ into the bush with a gun fighting‚ but Mnangagwa was on the ground".
Three men and a woman were also arrested after they allegedly booed Grace Mugabe at a ruling party rally.
Mugabe, who has held the presidency for more than two decades, remains the only leader many in the country have ever known.
Harvey Weinstein sued by actress over alleged hotel rape incident
She claims after the mogul learned she was an actress he offered to assist her with her career and asked for her phone number. He allegedly ignored her and "forcefully threw her" on the bed, pulled down her jeans and "started to orally copulate her".
The ruling party, ZANU-PF, said Chiwenga's statement suggests "treasonable conduct. meant to incite insurrection".
Chiwenga said: "We must remind those behind the current treacherous shenanigans that, when it comes to matters of protecting our revolution, the military will not hesitate to step in".
Grace Mugabe has drawn the ire of Zimbabweans for appearing to be out of touch.
Mnangagwa's ouster marked a dramatic shift in politics in Zimbabwe, where he had been a pillar of a military and security apparatus that helped Mugabe emerge as the nation's leader after independence from the U.K.in 1980.
Several armoured vehicles were seen driving down main roads outside the Zimbabwean capital on Tuesday, as tension erupted between Mugabe's regime and the military that has been a key buttress to his 37-year reign.
In a message posted on its website, Global Affairs Canada said the "situation is tense" in the city due to increased military activity and advised Canadians there to "remain indoors and monitor the media".
Mugabe's firing of Vice President Emmerson Mnangagwa, his right-hand man for almost four decades, stunned the nation.
The United States on Wednesday encouraged its citizens residing here to "shelter in place" amid political turmoil in the country.