Zimbabwe opposition leader Morgan Tsvangirai has said the crisis of governance in the country is deepening.
The strike was marred by violent incidents
He called for principled dialogue between his Movement for Democratic Change and the government to prevent anarchy and chaos.
Mr Tsvangirai told a news conference during a lunch break in his treason trial that the opposition would continue with protests which last week saw an effective nationwide strike called by the opposition.
Mr Tsvangirai said no amount of brutality and arrests of opposition supporters would discourage people, and the more repression there was the more it would rebound.
'Playing with fire'
Following last week's strike, hundreds of MDC activists have been arrested and many say they were tortured.
This "unprecedented violence" against political opponents has been condemned by the United States.
Following the strike, President Robert Mugabe warned the MDC not to instigate violence, saying: "Those who play with fire will not only be burnt but consumed."
Mr Tsvangirai is facing treason charges for allegedly plotting to assassinate President Robert Mugabe before last year's presidential elections.
A doctor working in a hospital in the capital, Harare, said more than 250 people have been treated there after being beaten by the security forces; many had broken fingers or toes, some had broken legs.
Two women described how men in military uniforms stripped them, beat them, and used guns to sexually abuse them.
The MDC says that children of opposition activists have been assaulted.
Zimbabwean police spokesmen Bothwell Mugariri said about 400 opposition members have been arrested since last week's strike.
He said many had been charged with malicious injury to property.
The police have denied the torture allegations.
"The police would want to interview and charge everyone who was involved in any kind of violence and we are not going to get distracted by people who organise violence and then cry foul when the law is applied to them," a spokesman said.
During the strike, stones were thrown at passing cars and a bus was set on fire.
The police also say that the offices of the ruling Zanu-PF party were set on fire in Chinhoyi, north of Harare, while explosives were found in the central town of Kadoma.
Zimbabwean human rights activist Tony Reeler says the attacks are focused on the MDC's local leadership.
Following the strike, the MDC gave Mr Mugabe until 31 March to agree to 15 demands including ending torture and depoliticising the police force or face further "popular mass action".
Tension is rising in Harare ahead of two by-elections this weekend in seats the MDC won easily in June 2000 elections.
Zimbabwe, once a regional breadbasket, now has massive unemployment, long fuel and bread queues and inflation of more than 200%.
Up to half the population, some seven million people, need food aid according to donors.