The government calls the campaign a clean-up effort, but critics at home and abroad say it is a violation of human rights and inspired by politics.
Police spokesman Austin Chikwavara on Friday said his force had started tearing down shacks and kiosks found at major crossroads in Chirumanzu, Umvuma and Lalapanzi in the Zimbabwe Midlands, between 200km and 300km south of the capital, Harare.
Another police spokesman, who was not identified, said police are also demolishing homes built without permission on some of the thousands of farms seized from their white owners for redistribution to black Zimbabweans.
However, Security Minister Didymus Mutasa maintained in the same broadcast that the month-long campaign was aimed only at cleaning out city streets and would not affect the government's rural strongholds.
The government's Operation Murambatsvina, or Drive Out Trash, has already left more than 250,000 city dwellers homeless in the winter cold.
Police have also arrested more than 30,000 vendors, accusing them of dealing in black market goods and attempting to sabotage Zimbabwe's failing economy.
President Robert Mugabe's former minister of information condemned the evictions on Thursday as barbaric.
Jonathan Moyo, addressing his first public meeting in the capital since he was fired in January, said the blitz was linked to a power struggle within the ruling party over who would succeed the 81-year-old Mugabe.
"It seems to be a directionless activity of some mischievous group which imagines it can profit by this in some mysterious way and position itself ahead of the pack in the succession game," he told the gathering at a Harare hotel on Thursday.
"It seems to be a directionless activity of some mischievous group which imagines it can profit by this in some mysterious way and position itself ahead of the pack in the succession game"
former information minister
Moyo, who spent five years as information minister, was fired for opposing Mugabe's choice of Joyce Mujuru as vice-president.
Moyo backed parliamentary Speaker Emmerson Mnangagwa, who represents a younger generation of ruling Zimbabwe African National Union-Patriotic Front members.
Opposition leaders say the eviction campaign is aimed at driving their supporters among the urban poor into rural areas, where they can be more easily controlled.
"The government wants to depopulate urban areas ahead of the 2008 elections and recreate a rural peasantry in which voters are brought under the control of local tribal leaders and Mugabe's militias," Sydney Masamvu, an analyst from the International Crisis Group think-tank, said in a statement on Friday.