Sydney-based Afghan lawyer Shahri Rafi – speaking on behalf of the extended family – said the husband and father had been found dead by his family in Kabul.
“They found him, he was beaten to death, he was found completely unconscious outside his door, the took him to the hospital but he had already died,” she told SBS News.
His family say he was an interpreter at one point working with Australia and a senior member of the Afghan military.
SBS News has protected the man’s identity, as his wife and children remain at risk.
His family say they appealed for Australia’s help and tried to secure him a humanitarian visa.
“He was involved with Australian army and Afghan army that made him [a] very obvious target,” Ms Rafi said.
Immigration Minister Alex Hawke said he would not comment directly on the case when questioned by reporters in Canberra.
“We don’t comment on individual cases – but we have done everything we can since 2013 to get people out,” he said.
“It is unsafe, it is dangerous and we condemn the Taliban and the acts that they are committing – the atrocities against minorities and against people who worked for many Western countries.”
Alex Hawke questioned over reported execution of interpreter
He said Australia would continue to work to “get people out” of Afghanistan seeking to flee the Taliban regime.
A Senate committee was told last week more than 26,000 applications had been made to the federal government from Afghan nationals looking to flee the country.
The number of applications is estimated to equal more than 100,000 people seeking Australia’s protection.
In August, the government announced 3,000 humanitarian places would be allocated to Afghan nationals, out of the 13,750 allotted in the annual program.
The government has insisted this figure is a “floor and not a ceiling” to the intake of Afghan visa holders.
Labor’s foreign affairs spokesperson Penny Wong on Wednesday said concerns around the safety of Afghans spoke to the need for more to be done to secure their safety.
“Regrettably we know too many people didn’t get out, I wish the government had acted sooner,” she told reporters.
“The government should be upfront in precisely how many people, how many Australian visa holders remain in the country.”
The extent of the man’s work with Australia is difficult to establish.
His family has burned almost all their documentation so that if they are found and captured in Kabul the Taliban can’t discover their identities.
He also has relatives in Australia – who have vowed to keep lobbying the federal government to provide them with humanitarian visas.