By Nick Bryant
BBC News, Sydney
Many asylum-seekers had been held on the Pacific island of Nauru
Australia has ordered an investigation into claims that up to 20 Afghan asylum-seekers were killed by the Taleban after being returned home.
A television documentary reports that those who died were among 400 Afghan asylum-seekers denied entry to Australia by the former government.
Their fate was examined by a social research group, the Edmund Rice Centre, which says it has proof of nine deaths.
The policy under which the Afghans were returned home has since been dropped.
The previous Howard government's so-called Pacific Solution policy detained people with asylum claims on islands in the Pacific, preventing them from setting foot on Australian soil.
Incoming Prime Minister Kevin Rudd cancelled the Pacific Solution and the forced returns policy.
The deaths were brought to light by a television documentary due to air on the SBS channel later this month.
About 400 Afghans detained at the Australian detention centre on the Pacific island of Nauru were returned to their homeland, having had their asylum claims rejected.
According to many in their own accounts, they were assured by Australian immigration officials that it was safe for them to return home, and told that they would be held in detention for the rest of their lives if they failed to do so.
But an investigation by the social justice group, the Edmund Rice Centre, has found that some were killed by the Taleban.
It documented the deaths of nine of the failed asylum seekers at the hands of the Taleban and believes the true figure is actually closer to 20.
The investigation also found that many Afghans who were returned home are hiding in Pakistan, or were forced to move between there and Afghanistan in order to evade capture.
They include an Afghan man whose daughters were killed in an attack on his home near Kabul, after his bid for asylum was rejected by Australia in 2002.
The director of the Edmund Rice Centre, Phil Glendenning, has said that much of the information used to locate returned asylum seekers had come from sympathetic immigration officials, angry about the controversial asylum policies of the Howard government, which introduced the Pacific Solution.
The new immigration minister, Chris Evans, has asked his department to look into the claims.
Meanwhile, his predecessor Phillip Ruddock said that "mistakes were possible," but added that Australia's asylum system was "robust and credible".
He said that the United Nations Refugee Convention did not prevent asylum seekers from being returned to dangerous places.