Results showed the ruling party win a majority of parliamentary seats, but the opposition declared victory in the presidential race
Three people have been killed as Zimbabwe's president blames the opposition for the violence after the country's general election.
The military has swept into the capital Harare to disperse protesters after the Zanu-PF won a parliamentary majority in the vote.
Soldiers have opened fire with guns, water cannons and tear gas - as opposition demonstrators burned cars and threw rocks at helicopters hovering above.
The United Nations has urged political leaders and Zimbabweans to reject any form of violence.
Weeping family members have been seen at the Parirenyatwa Hospital in the capital, where a man's body lay on a stretcher.
He has been locally identified as street vendor Ishmeil Kumeni (42) who was caught in the crossfire.
Brighton Chizhande, chairman of the Zimbabwe Doctors for Human Rights, says the organisation has confirmed one death from a gunshot wound near the heart.
They are following up reports that four others have died.
Mr Chizhande added that the injured include people with deep wounds in the shoulder, buttocks and another suffered a "gunshot wound to the penis".
President Emmerson Mnangagwa said in a statement that the opposition under Nelson Chamisa is responsible for the disturbance of national peace" meant to "disrupt the electoral process".
He earlier tweeted: "We must all demonstrate patience and maturity, and act in a way that puts our people and their safety first".
At this crucial time, I call on everyone to desist from provocative declarations and statements. We must all demonstrate patience and maturity, and act in a way that puts our people and their safety first. Now is the time for responsibility and above all, peace— President of Zimbabwe (@edmnangagwa) August 1, 2018
Zimbabwe holds parliamentary and presidential elections separately, with the electoral commission saying the outcome of the latter will be released "sometime tomorrow".
Official results show the ruling Zanu-PF party won the most seats in the parliamentary ballot, but the opposition Movement for Democratic Change (MDC) rejected the outcome and claimed there had been fraud.
Police have invoked a strict security act that forbids public gatherings amid the violence.
The opposition Movement for Democratic Change has told reporters that Mr Chamisa is "shocked" by the events in Harare.
A spokesman said: "We are seriously meant to wonder that this means. Are we at war?".
The opposition says it condemns violence in all its forms.
The elections in Zimbabwe were the first since Robert Mugabe was forced out of his presidency last year.
Additional reporting: Stephen McNeice