A UN envoy visiting Zimbabwe has said that the authorities could have taken steps to minimise the human impact of a controversial slum clearing programme.
Dr Tibaijuka said the people were anxious for their lives to improve
Anna Tibaijuka told the BBC that while urban development was important, the government should have followed better procedures to avoid human misery.
Her visit follows international anger over the demolitions, which have left an estimated 275,000 people homeless.
Officials say the moves are aimed at removing criminals and reviving cities.
Ms Tibaijuka said she would submit her report to the UN secretary general, Kofi Annan.
Her visit coincides with Amnesty International reports that three more people have died during the clearances.
On Thursday Ms Tibaijuka visited the Porta Farm site where two women - one pregnant - and a boy were reportedly killed, but said she was unable to confirm the report.
Over breakfast with thousands of former residents of another site at Caledonia Farm, she said something had to be done for the displaced people.
"I think it was very clear that they all seem anxious to get their lives improved," she said, quoted by AFP news agency.
"When I asked them if they were happy, I got a resounding no. So definitely there are challenges that we have to sort out," she said, quoted by AFP news agency, after visiting the Caledonia Farm site.
In a separate move, the World Food Programme (WFP) said Zimbabwe's current food shortages made it one of the most worrying countries in the world.
The demolition programme began a month ago. At least three other children have been killed during the operation.
Mr Mugabe says the slums were cleared to root out crime
Thousands of the displaced people are now living on the streets, while others have gone back to rural areas, and some have moved into unaffected parts of the cities.
UN Security Council members criticised the demolitions.
Britain's ambassador to the UN, Emyr Jones-Parry, said the government was to blame for many of the problems facing Zimbabwe.
Acting US ambassador Anne Patterson said America was deeply concerned about the demolition scheme and urged the government to begin a dialogue with the opposition.
Meanwhile South African has hit back at accusations that it has been silent about Zimbabwe's problems.
"President Thabo Mbeki has been very clear on this - he went to Zimbabwe twice, and in the presence of President Mugabe expressed his displeasure about things that were going on in Zimbabwe," South African presidential spokesman Bheki Khumalo told the BBC.
"The notion that we have not spoken out is not true.