The foreign affairs minister says the government is trying to verify reports that an alleged Australian Islamic State (Isis) recruiter has been killed in the Middle East.

Mohammad Ali Baryalei, alleged to be the most senior Australian involved in the Isis conflict in Iraq and Syria, reportedly died four or five days ago.

Baryalei has been accused of recruiting Australians to fight alongside Isis forces.

The foreign minister, Julie Bishop, was unable to confirm whether he had been killed.

Speaking at the national press club, Bishop said: “The Australian government will of course pursue the details of this matter. The allegations that he has been killed.

“But we will also be unrelenting in finding the details of where he’s been, who his contacts are, who he’s called, and let’s face it, that’s why the retention of metadata is going to be absolutely essential for us to carry out the kind of work that is required to ensure that we can keep Australia as safe as possible.”

She added: “We are currently seeking to verify those reports. So I can’t confirm at this stage.”

A Sydney friend of Baryalei, Abdul Salaam Mahmoud, posted on Facebook on Tuesday night that he had been “martyred”.

“I’ve just received the news that our beloved brother Mohamed Ali who was recently strongly attacked by Australian media has been martyred,” he wrote.

“He was a brother a friend and our leader in street dawah Sydney.

“Today we shall celebrate his martyrdom with tears of joy and sorrow. Oh Allah accept him as another green bird.”

News of his death was also tweeted by a British-based researcher Shiraz Maher, from the International Centre for the Study of Radicalisation at Kings College in London.

It is believed that at least 15 Australians have been killed in the conflict against Isis since it began.

“Australians who leave this country to fight in Iraq and Syria are putting themselves in mortal danger,” Bishop said.