Zimbabwe's President Robert Mugabe has strongly defended the demolition of illegal houses, which the UN says has left some 200,000 people homeless.
People have been evicted and their buildings destroyed
At the state opening of parliament, he described the three-week blitz as "a vigorous clean-up campaign to restore sanity" in Zimbabwe's cities.
Opposition MPs boycotted his speech as part of a two-day general strike, called in protest at the demolitions.
Many shops and businesses, however, were open as usual.
Traffic is reported to be lighter than usual and there is a heavy police presence in poor areas during the strike, called by an alliance of opposition parties, trade unions and lobby groups.
During the three-week crackdown, bulldozers have razed shantytowns and markets in the capital Harare and armed police have made some residents knock down their own houses.
A Catholic priest told the BBC News website that many people were living rough, surrounded by a few possessions, despite the cold winter nights.
"The current chaotic state of affairs where small- to medium-scale enterprises operated outside the regulatory framework and in undesignated and crime-ridden areas could not be countenanced much longer," Mr Mugabe said.
The president also promised "to deal with the emergence of more sophisticated forms of corruption and crimes such as electronic money-laundering, electronic funds transfer fraud, dissemination of offensive materials and even cyber-terrorism".
He confirmed plans to re-introduce an upper house of parliament, which correspondents say is aimed at strengthening his grip on power.
The usual rush hour traffic in Harare was far lighter than normal and there are reports that, while many factories are open, up to half their workers have stayed at home.
Robert Mugabe defended the 'vigorous clean-up campaign'
The situation seems to be the same in the second city of Bulawayo, where normally busy shopping areas are quiet.
The government has put on a show of force - with military helicopters clattering overhead - leaving people in no doubt that those who do strike could face punishment, he says.
Police have warned they will deal "ruthlessly" with any street protests.
The government says the demolitions are necessary to clean up Zimbabwe's urban areas and crack down on those involved in illegally trading foreign currency and scarce foodstuffs, such as sugar.
Some 30,000 people have been arrested.
The sweep has been heavily criticised by church groups and opposition parties, which have combined to form the "Broad Alliance" and call the strike.
They say the crackdown is aimed at driving opposition supporters back to rural areas, where they have less influence.
The UN has demanded that Mr Mugabe stop the eviction operation, which it describes as a new form of "apartheid".
The UN Human Rights Commission estimates that up to 200,000 people may have been made homeless by the operation.