Victoria Police told SBS World News officers tried to arrest the man in the suburb of Epping as part of an ongoing investigation at midday Friday.
They started negotiating with the man before he “returned back inside”, a spokesman said.
Police believe he’s armed with a handgun but could not confirm whether he’s holding a woman and four children hostage inside, as some media reports have indicated.
The area has been cordoned off.
“We will be there for some time,” the spokesman added.
