Political and police leaders in Victoria have commended the officers wounded in a shootout with the Brighton siege gunman.
A special operations police officer who was shot in the face, head and neck during the Melbourne siege will need surgery.
Two of his colleagues were also wounded, with one undergoing hand surgery on Monday, the police union says.
Yacqub Khayre - who was on parole - killed a receptionist at the Buckingham Serviced Apartments in Brighton and held a woman hostage about 4pm on Monday afternoon.
When he left the building, he fired at police, wounding three of them before they killed him.
Deputy Commissioner of Specialist Operations, Shane Patton, said the special operations officers "showed great courage" during the seige.
"They were decisive, they were swift when confronted by a terrorist, armed with a firearm, who shot at them," he said.
"Police Command, and indeed I think I speak for all members of Victoria Police, are immensely proud of the way out members responded on that occasion and the courage they showed.
"No one goes to work expecting to be shot at. It would have been exactly a very traumatic event for them."
Victorian Police Association secretary Wayne Gatt said the injured officers will require rehabilitation.
Watch: Police update on Brighton attack
Sergeant Gatt also commended the work of the first responders who ensured the wider public was kept safe.
"The injuries last night were not critical or life-threatening. However, they were serious injuries that will require a level of rehabilitation and, certainly, a level of repair," he said.
"They are brave and courageous... they put themselves between those in the community who seek to harm us and their personal safety second."
Victoria Police Chief Commissioner Graham Ashton said police did an "outstanding job" and he has confidence in the way they handled the situation.
"Someone comes out firing a shotgun, that's an extremely high-risk situation," he said on Tuesday.
"They've taken the necessary action at the scene and acted very bravely in doing that."
Premier Daniel Andrews said there was no way to "eliminate risk", just to mitigate it and said he had nothing but praise for the way police acted.
"What is beyond question in this incident, and at all times, is the professionalism, bravery, courage and effectiveness of our specialist police forces in this state," Mr Andrews told reporters.
"But be in no doubt the special operations group and others last night have put themselves in harm's way to keep the rest of us safe."
Melbourne siege gunman tampered with GPS
Long-time criminal Yacqub Khayre tampered with his GPS ankle bracelet during the terror attack.
Police are investigating whether Khayre deliberately lured them into a deadly ambush after it was revealed he had booked a female escort, whom he took hostage, and sparked an alert on his tracker.
Commissioner Ashton says it is a "possibility" the 29-year-old wanted to lure police into a deadly shootout.
"[There was] certainly a booking made to see an escort at the premises. He's then turned up at the premises with a firearm," he said.
"That's all been weighed into the calculations, but we haven't found anything like a note or any comment around that."
Watch: Gunman should not have been on parole: PM
Officers had earlier found the body of a 36-year-old Chinese-born Australian clerk in the foyer.
"He appears to [have been] in the wrong place at the wrong time," Commissioner Ashton said.
Corrections Victoria confirmed Khayre's GPS tracker was tampered with while the siege was under way.
IS claimed responsibility for the attack online, but Commissioner Ashton downplayed their statement.
"We're aware of [online] them having claimed responsibility, but then they always tend to jump up and claim responsibility every time something happens," he said.
"But he's also made statements last night around (rival organisation) al-Qaeda."
On Monday afternoon, the Seven Network took a phone call in its Melbourne newsroom from a woman who said she was in a hostage situation before man came on the line saying: "This is for IS, this is for al-Qaeda."
Khayre once spent 16 months on remand before being acquitted of a 2009 plot to attack the Holsworthy army barracks in Sydney.
He was jailed in 2012 over a violent home invasion and released six months ago.
Mr Ashton said Khayre had been on parole since being released from prison in November and "there was nothing wrong with his parole until yesterday".
Watch: Counter-terror police investigating Melbourne gunman
Prime Minister Malcolm Turnbull said there were "very grave questions" about why Khayre was on the streets.
"How was this man on parole? He had a long record of violence," he said.
"He was known to have connections, at least in the past, with violent extremism."
Premier Andrews promised to look at every part of the parole system but said it had already worked to keep Khayre in jail longer than his minimum sentence.
"(Since his release) he's been compliant, including drug tests, attending appointments and observing a curfew," Mr Andrews said.
Watch: Daniel Andrews on Brighton siege