Public discontent has grown in Zimbabwe with President Emmerson Mnangagwa, who has struggled to fulfil promises of economic prosperity and more political freedoms.
Zimbabwean police on Wednesday used batons, tear gas and water cannon to beat up and disperse supporters of the main opposition party who had gathered outside their party headquarters in the capital to listen to a speech by their leader.
Movement for Democratic Change (MDC) leader Nelson Chamisa said the latest police action showed that President Emmerson Mnangagwa's government was afraid of its citizens.
The MDC accuses Mnangagwa of adopting the heavy-handed tactics of his predecessor, Robert Mugabe, who ruled Zimbabwe for 37 years until his generals turned against him in a coup two years ago. Mugabe died on September 5.
On Sunday, Mnangagwa, defended his record in an opinion piece carried by CNBC Africa, saying his administration was opening up political and media space.
But police have this year banned several MDC gatherings, saying they feared the events would turn violent after fuel protests in January became deadly and more than a dozen people died following a security crackdown.
Hundreds of police blocked roads leading to MDC headquarters in Harare but supporters continued to gather, singing and chanting before the arrival of party leader Chamisa.
A few minutes after Chamisa entered the party building, police charged the crowd with batons and fired tear gas, causing a stampede.
Several people were injured. The Zimbabwe Lawyers for Human Rights group said it had deployed lawyers to represent at least eight people that were arrested by police.
Police spokesman Paul Nyathi declined to comment.
'End is nigh'
After Wednesday's clashes, Chamisa told reporters and party officials at the MDC offices that time would come when the MDC would no longer seek police permission for its gatherings.
"What this tells you is that we [have] a rogue regime. What this tells you is that we are in a pariah state," he said during a speech he dubbed hope of the nation address.
"When you see a regime that is so scared of its own people, you must know that the end is nigh."
Critics accuse Mnangagwa's government of intolerance of dissent, pointing to protest bans and arrest of dozens of activists since January on charges of subverting the government.
At a magistrates court in downtown Harare, prosecutors withdrew subversion charges against activist pastor Evan Mawarire, one of several people who was arrested during the January fuel protests, his lawyer told Reuters.
Political tension is rising in Zimbabwe, where citizens are grappling with a severe economic crisis that has seen rolling power cuts lasting up to 18 hours a day and shortages of foreign currency, fuel and medicine.
Most public sector doctors have been on a strike over pay since September, paralysing government hospitals where the poor seek treatment. Other public sector workers are demanding US dollar-indexed salaries to protect them from soaring inflation.
Critics say Mnangagwa has failed to keep promises he made during last year's election campaign to revive the economy by pushing through economic reforms, attracting foreign investment to create jobs and rebuilding collapsing infrastructure.