Police have shot dead three people after an ambush at a remote property on Queensland's Darling Downs in which two officers and a neighbour were killed.
Earlier on Monday, four officers were at the isolated rural property to investigate reports of a missing person believed to be a former school teacher from NSW and were met with a hail of gunfire.
Police returned fire but the two officers were critically injured and died at the scene.
Another two officers were wounded when at least two gunmen opened fire at the rural property at Wains Road in Wieambilla at 4.45pm, about 300 kilometres west of Brisbane.
It is understood the four officers who attended the property were shot at from inside a house as they walked up a driveway. Authorities said a siege situation then ensued at the property and specialist police officers and PolAir responded.
"Two males and a female were fatally shot during a confrontation with police shortly after 10.30pm," police said in a statement early on Tuesday morning.
It's understood that three attackers were killed in a firefight with officers following a manhunt.
Police Commissioner Katarina Carroll said the horrific incident was devastating for the victims' families and the entire organisation.
The commissioner fought back tears as she confirmed the initial deaths of the three people, including two police officers, at the late-night media conference on Monday.
"I would like to also pay tribute to all police and first responders who assisted at the scene and are continuing to respond this evening.
"Tragically, this is the largest loss of life we have suffered in one single incident in recent times... It is devastating news.
"It is sad reminder of the unpredictable nature of policing and the incredible dangers our officers face while protecting our community," she added.
An emergency declaration remained in place on Tuesday morning for the Wieambilla area and a crime scene had been established at the property.
Slain Queensland officers were 'very junior in service'
Queensland Police Union president Ian Leavers on Monday night said "the behaviour of these murderers tonight is absolutely unacceptable".
He said the two officers, who he described as young and "very junior in service," had had their life tragically cut short. Both officers were in their 20s.
After they were shot, it's believed the gunmen stood over the officers' bodies and fired further rounds into them, execution-style, the Australian reported.
Two other officers managed to escape with one being grazed by a bullet while another managed to survive the onslaught and hide away.
The gunmen were reportedly wearing combat-style camouflage.
A six person killed in the fire fight is believed to be a neighbour.
It's since been revealed the officers attended the property at the behest of their NSW counterparts as part of a search for missing Dubbo man Nathaniel Train, 46. His brother was believed to live at the Wains Rd property, the Daily Telegraph reported.
Police memo reveals 'shock and disbelief'
Mr Leavers shared an internal memo with Queensland officers expressing the immense sadness felt across the force.
"These officers’ tragic, needless and senseless murders have already been felt deeply across Queensland and all over Australia," the memo said, according to the Courier Mail.
"Our thoughts are also with police who bravely contained and managed the subsequent operation that has now resulted in the deaths of all the offenders.
"We are all in a state of shock and disbelief. To be here tonight and know that two brave police both under the age of 30 have needlessly lost their lives affects all our emotions."
He described the killings to his colleagues as "ruthless, calculated and targeted execution(s)".
'Deeply distressing': PM and Peter Dutton pay tribute
Prime Minister Anthony Albanese had earlier said it was a heartbreaking loss for the families and friends of the Queensland Police officers who lost their lives in the line of duty.
"Terrible scenes in Wieambilla and a heartbreaking day for the families and friends of the Queensland Police officers who have lost their lives in the line of duty. My condolences to all who are grieving tonight – Australia mourns with you," he tweeted.
Opposition leader Peter Dutton, a former Queensland police officer, was also moved by the tragedy.
"Deeply distressing news coming out of western Queensland tonight with those police officers who have been murdered," he wrote. "Police officers face danger every day to keep us from it."
Premier Annastacia Palaszczuk said the deaths were a "horrible tragedy" as Western Downs regional council mayor Paul McVeigh said his community was shattered. "It's an absolute tragedy in our community," Cr McVeigh said.
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