The Zimbabwean government says that the security forces' response to this week's protests, where a number of people are allegedly dead, is just "a foretaste of the things to come".
The news of a violent breakdown has arisen despite the government blocking social media.
Local rights groups said at least 1
The protests were triggered on Monday by a sharp increase in fuel prices.
- Despair, anger and anxiety in Zimbabwe's fuel queue
- The most expensive fuel in the world?
President's spokesman George Charamba spoke to the state-owned Sunday Mail newspaper, accusing the opposition Movement for Democratic Change (MDC) of the violence that accompanied the protests.
"The MDC management has consistently stated the announcement that they will use violent street action to reverse the outcome of a vote," he said.
The opposition rejected a ruling in August, confirming that President Emmerson Mnangagwa had beaten MDC candidate Nelson Chamisa.
During the week, the riot police collided with protesters in the capital Harare and the southern city of Bulawayo after they had lit fires and blocked roads by rocks.
On Thursday, Chamisa tweeted that his thoughts were "with the victims of violence".
"Despite the vitriol," he added, "we maintain a dignified position that fits our role as led by the people."
The United Nations has called on the government to stop the "excessive use of force" by security forces in connection with door-to-door search and use of live ammunition.
Why did the fuel price rise?
A week ago, President Mnangagwa announced that the fuel price would more than double.
The price increase was aimed at alleviating deficiencies caused by an increase in fuel consumption and "violent" illegal trade, he said.
But many Zimbabweans, who were worn out by many years of financial difficulties, suddenly found that they could not even afford the bus fare for work.
New prices mean that Zimbabwe now has the most expensive fuel in the world, according to GlobalPetrolPrices. com
They feel that the president, who has been on a tour of Russia and the Asian countries, does not live up to his promises after his election last year in controversial polls.
He struggles to revive the economy, experiencing high inflation while wages have stagnated.
Internet access was intermittent during the week, but people found that they could not use social media and the WhatsApp messaging platform, which has become a common way of sharing news.