Tunis: A second Australian man has reportedly died fighting with Kurdish forces in Syria, less than two months after he joined the battle against the Islamic State group.

Described as a "beloved brother who came from far away to do what had to be done," 23-year-old Reece Harding reportedly died on June 27 when he stepped on a land mine during night operations with the YPG (People's Protection Units) in north-eastern Syria.

His death was announced in a post on the Lions of Rojava Facebook page, accompanied by photographs showing the man purported to be Mr Harding in combat gear carrying a Kalashnikov, standing with his unit.

Fairfax Media has not yet been able to confirm his death, although his father Keith Harding told the ABC he had received a message on Monday telling him to call an overseas number. When he did he was told his son had been killed.

The Gold Coast family are still coming to terms with what had happened, he told the ABC, describing feelings of "numbness, disbelief that it's happening."

"Everybody in his unit praised him for his courage and said that he was hard to match," the death notice reads. "A man who stood up for his beliefs and therefore joined the fight with the brave warriors of the YPG."

One of his comrades from the 'Sabotage Battalion' commented: "He turned to me before going into the fight and bumped fist as if to say we are in this together."

The exact location of the night-time operations in which Mr Harding was killed and five others were injured is unknown, but at the time, the YPG were engaged in fierce battles on the outskirts of Hassaka after Islamic State launched an assault on the city.

Areas in Hassaka are split between the control of the Syrian regime and Kurdish authorities, with a mixed population of Arabs, Kurds and Christians.

To his Kurdish colleagues he was known as Heval Bagok Australi. His unit voted to revenge his death, with another Australian reportedly fighting with the YPG, Ashley Dyball, or Heval Ahmed, quoted by the Lions of Rojava as saying: "I have his sawn off shotgun and will use it to avenge him."

Mr Harding is the second Australian to die fighting with the YPG forces in Syria. Ashley Johnston who was killed in the battle between the YPG and ISIS in the city of Tel Hamis near the Syria-Iraq border on February 24.

Fairfax Media has approached YPG officials for comment on Mr Harding's death but we did not received a response by the time of publication.