The crackdown on illegal structures in Zimbabwe will move this week to the rich northern suburbs of the capital, Harare, police say.
Officials blame street vendors for wrecking the economy
A police spokesman says that many houses have been turned into offices without planning permission.
Correspondents say Zimbabwe inherited strict colonial planning laws, but has failed to enforce them in recent years.
Some 200,000 people have lost their homes, the United Nations says. So far, mostly poor areas have been targeted.
Many people are living on the streets, while other have returned to their rural homes, encouraged by the government.
The opposition says Operation Murambatsvina [Drive out rubbish] is intended to punish urban voters who rejected President Robert Mugabe in March polls.
Mr Mugabe says the blitz is needed to "restore sanity" in urban areas overrun with criminals.
Officials also want to stamp out the black market, which they blame for Zimbabwe's economic meltdown.
"We are moving everywhere, including the northern suburbs and some rural areas, everywhere where there is an illegal structure, we will get there," Harare police spokesman Whisper Bondayi told the AFP news agency.
The state-owned Herald reports Inspector Bondayi as saying that some of these "illegal" offices are engaged in shady deals.
He says the offices should return to the city centre, which many businesses have fled in recent years due to overcrowding and rising street crime.
Offices signs are now a common sight in previously residential areas.
In colonial times, the northern suburbs were reserved for whites but many rich black people now own homes there.
The Herald reports that over the weekend, police destroyed outside toilets in the commuter town of Chitungwiza, south of Harare.
Many of the structures targeted for demolition have been illegally built in gardens and the police mistakenly believed the toilets were illegal extensions, the Herald says.
Angry women confronted the policemen responsible, the paper says.
Mbuya Mushambi, 80, says that she was advised by her bank to build extensions in her Harare backyard to rent out to earn the money to look after her grandchildren.
Their parents had died from Aids-related problems.
These extensions have now been demolished by the police.
"This was everything I had - more importantly, this was everything these children had. What will we do?" she asked.
The United Nations children's fund (Unicef) has given her blankets and cooking materials.
"It all helps and I am very grateful - but I preferred it when I could look after my own," said Ms Mushambi.