The Immigration Minister, Amanda Vanstone, says the Edmund Rice Centre has made similar claims before, but never in enough detail for her department to pursue.
The centre's director, Phil Glendenning, says the department has all the information it needs.
“In a few cases, there are individuals who believe that their lives are under such danger and threat that they don't want us to hand over their name, given the fact that these people believe that it was the Australian Government that put them in that situation and so they have real fears about what the Australian Government might do with that information,” Mr Glendenning said.
The government says it will investigate the claims that failed asylum seekers were killed after returning to Afghanistan if provided with further information, Foreign Minister Alexander Downer says.
Mr Downer said he had only heard the claims through the media.
"If those making the claims wish to approach us to provide us with all of the details we would obviously be happy to look into people being killed and the circumstances in which they might have been killed," he said.
Mr Downer said the government would need information on who the asylum seekers were, how they were killed and the circumstances that led to them coming to Australia and being refused asylum.
Asylum seeker laws
Meanwhile Mr Howard has pleaded with backbenchers to maintain party unity as government MPs threaten to cross the floor over new hardline boat people asylum seeker laws.
The issue will be debated in federal parliament tomorrow, but at
least four backbenchers told a coalition meeting today they did not
support the new laws.
Mr Howard has ruled out making any more changes to accommodate their concerns, but urged them to abstain from voting rather than cross the floor of parliament.