Grave concerns are held for an Australian prisoner of war who is suspected to have been killed by Russian forces in Ukraine.
The Australian government said it is making urgent enquiries following reports of Melbourne teacher Oscar Jenkins' death.
The 32-year-old was captured in social media videos last month visibly bruised and shaken while being interrogated and beaten by a Russian-speaking captor.
"These reports have not been verified, but we continue to have grave concerns for Mr Jenkins' welfare," DFAT said in a statement on Tuesday evening.
The Russian ambassador was called into DFAT in a bid for clarity on the reports and to "reiterate Australia's expectations that Russia will comply with its obligations under international law".
"The Russian Federation is obligated to treat all prisoners of war in accordance with international humanitarian law," the statement read.
"DFAT is continuing to provide consular support to Mr Jenkins' family during this difficult time."
In the social media video circulated last month, Mr Jenkins was shown speaking a mix of broken Russian and English.
"Live in Australia and Ukraine. I'm a teacher," he said.
The man asked Mr Jenkins in Russian how it was he came to be in Kramatorsk, a town 700km east of Kyiv in the Donbas region, near the Russian-Ukrainian frontline.
Standing in army fatigues in a forest, Mr Jenkins tells the man he wanted to help Ukraine and had previously lived in China.
According to a LinkedIn profile matching Mr Jenkins' details, he attended Melbourne Grammar School before working for seven years as a university lecturer in Tianjin, China.
Mr Jenkins was deeply involved with the Toorak Prahran Cricket Club in Melbourne, winning a senior premiership with the club in 2013-14 and serving as a junior coach for three seasons, his LinkedIn stated.
Mr Jenkins is the first Australian combatant reportedly captured by Russian forces in Ukraine.
His death would mark the first for an Australian prisoner of war in more than 70 years.
Russia has said foreign citizens fighting for Ukraine will be prosecuted as mercenaries and face up to 15 years in jail, which would contravene international law.
