Sprawling tent communities have turned Kabul into one of the world's fastest-growing cities, as thousands of Afghans return to their native country from refugee camps in Pakistan and Iran.

The city's population has soared from about 500,000 in 2001 -- when the Taliban fell -- to more than 3 million, according to census data from the Afghan Central Statistics Office.

Each year, hundreds of thousands of refugees return to the country from Iran and Pakistan, where the governments have shut down refugee camps and told Afghans to leave.

In 2007, roughly 250,000 Afghans were deported from Iran despite not having identification papers from their native country, according to the office of the United Nations High Commissioner for Refugees (UNHCR).

Many of those refugees now live in camps on the outer edges of Kabul, desperately searching for employment. Roughly 60 per cent of Afghan returnees are living on less than $1 each day, according to a 2007 survey by the Afghanistan Independent Human Rights Commission. Only about 38 per cent said their household had a steady income.

More than half reported having no access to safe drinking water.

A leader of one of the camps told ۴ý that humans should never have to live in such a filthy environment.

"As you can see, animals live better than we do," he said.

Many children in the sprawling camps have been infected with parasites carried by sandflies. CTV cameras filmed a two-year-old child whose cheeks had been ravaged by disease.

Now, apartment blocks have begun springing up around the camps, with three-room apartments selling for $40,000.

A man named Mozafar in one camp said he sometimes dreams of owning such a place, but knows it likely will never happen.

"We're just looking up and dreaming of the good life," he said.

In some areas of Kabul, developers have sought to build homes in the camps and have told residents to move. But many of the residents have already been displaced from Iran and Pakistan.

Kabul's booming population will likely continue to grow. According to the UNHCR, there are currently about 2 million registered Afghans in Pakistan who have been told to return to their native country by the end of 2009.

With a report by CTV's Paul Workman in Kabul