A five-day blitz against street vendors and flea markets already has sparked clashes between the traders and police, and unrest has been reported elsewhere. Police Chief Superintendent Oliver Mandipaka said Monday that 9,653 people have been arrested.

On Tuesday, the government set a June 20 deadline for demolishing unauthorized buildings in Harare unless the residents appeal and receive a grace period. The demolitions could evict more than a million urban poor in the middle of the Zimbabwe winter.

"The attitude of the members of the public as well as some city officials has led to the point whereby Harare has lost its glow. We are determined to get it back," government-appointed Mayor Sekesai Makwavara said in a statement.

She said all "illegal structures" would be demolished during the operation, which was dubbed "Operation Marambatsvina" or "drive out rubbish."

The crackdown on street traders — who include teachers and other professionals unable to make a living at their old jobs — is aimed at crushing the black market for scarce staple goods like maize meal, sugar and gasoline. The government claims the traders are not licensed and blames them for sabotaging the economy.

Lovemore Madhuku, a university teacher who leads the National Constitutional Assembly, an umbrella group of organizations seeking radical reform, warned the demolitions might ignite public anger on a scale unseen since the African nation gained independence from Britain in 1980.

"I think now people are really going to react," he said.

The cleanup ultimatum revived memories of the 1985 elections when ZANU-PF mobs, reacting to comments by longtime leader Robert Mugabe, forced thousands of families suspected of supporting the opposition from their township homes until they could produce ruling party cards. An unknown number of people were killed while police refused to intervene.

Township resident Petros Nyoni said the mood in Harare's crowded suburbs was tense Tuesday, with workers already angry at a police crackdown on the commuter minibuses that are the mainstay of the transport system.

Hundreds of the taxis have been grounded by lack of fuel at filling stations while many more have been impounded at roadblocks for allegedly being unfit to drive.

"There is a very big crisis. People are so desperate they are jumping through (minibus) windows or onto the roof carriers," he said.

After seven years of unprecedented economic decline, 80 percent of the work force is unemployed and 4 million of Zimbabwe's 16 million people have emigrated. Agriculture, once the mainstay, has been hard hit by Mugabe's seizure of 5,000 white-owned farms for redistribution to blacks.

The government last week announced a 45 percent devaluation of the Zimbabwean currency against the dollar, a ban on luxury imports and heavy subsidies for agriculture and exporters.

Michael Davies, chairman of the Combined Harare Residents Association, said more than half of the capital's population of 2 million to 3 million people live in housing marked for demolition. He said in some cases rents from the buildings were the only means of survival for elderly owners.