06/06/2017 9:10 AM AEST | Updated 06/06/2017 12:01 PM AEST

Police Sceptical Of ISIS Link To Melbourne Siege

'They always tend to jump up and claim responsibility every time something happens.'

Police are probing possible terror links to the fatal Melbourne siege overnight, but the Victorian police chief has voiced his doubt that ISIS was actually involved.

Police shot dead gunman Yacqub Khayre, 29, at an apartment block in Brighton just before 6pm on Monday, ending a two-hour hostage situation and rescuing a woman who was held captive. Police had earlier found the building's attendant shot dead in the foyer.

Before being shot, the gunman made a call to Channel 7's newsroom and reportedly said: "This is for IS. This is for al-Qaeda."

On Tuesday, the ISIS-linked news outlet Amaq reported that the Middle Eastern terror group has claimed responsibility for the attack, and called the gunman a "soldier" of the group.

Considering the gunman's phone call and the ISIS claim of responsibility, police confirmed they would investigate terrorism as "one line of inquiry". However, during a Tuesday morning press conference, Victoria Police Chief Commissioner Graham Ashton cast doubt on the ISIS links.

"We're aware of, online, [ISIS] having claimed responsibility, but then they always tend to jump up and claim responsibility every time something happens," Ashton said.

"We note that that has happened but he's also made statements la night around al-Qaeda. We believe that he has made a call to Channel Seven making those sorts of comments as well. That's why we're treating this as a terrorism incident."

"There is nothing that we've found thus far that would suggest to us that this was anything that was planned or done in concert with others. We believe at this stage from the information we have that he was acting alone and there isn't a sort of ongoing threat in relation to any plot or anything around this individual."

Ashton said the gunman "hasn't been someone who has been a major concern in relation to terrorism aspects", saying it was "more general criminal offending he's been involved with".

Regarding the ISIS claim the gunman was a "soldier" of the group, Ashton was again sceptical.

"It's a statement made by them. We've factored that into this but again it's the sort of thing they jump up and say a lot. We're not seeing anything indicating that he's got some message from overseas to do this at all but, again, early days," he said.

"We've got material that's seized. We'll go through that and work it out."

Ashton also downplayed any link to the recent Manchester and London terror attacks.

"[There is] nothing to suggest that. Whether the ideology was fired up from last week, it's too early to say but it's one of those avenues of inquiry," he said.

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