'This is squarely in his court': Cop killer gave police no choice but to shoot

Police say they were were left with no choice but to shoot when negotiations with a "highly motivated" suspected cop killer, who "had issues", failed on Tuesday morning.

Speaking to the media on Tuesday afternoon Queensland Police commissioner Ian Steward and deputy commisioner Steve Gollschewski said expert officers had spent the night trying to negotiate with Rick Maddison to surrender after a 21 siege sparked by the fatal shooting of Senior Constable Brett Forte on Monday.

Deputy commissioner Gollschewski said Maddison had taken matters into his own hands at about 11am on Tuesday, firing at police before being shot dead himself.

"Numerous officers called on him to put his weapon down and he chose not to," he said. Maddison also fired shots at police.

A gunshot wound to Maddison's chest brought the siege to end, which began when he allegedly shot dead Senior Constable Forte at Seventeen Mile near Toowoomba in the Lockyer Valley on Monday afternoon.

Constable Forte leaves behind three small children as well as a wife, father and brother in law, all of whom are also police officers.

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A second police officer injured

Another officer was injured in the shootout on Tuesday when a high-calibre bullet pierced armoured glass on a police vehicle, leaving a minor wound on their face.

Maddison had a criminal history, was known to police and was known to have violent incidents in his past.

He was wanted by police when he fired on a car carrying Constable Forte on Monday. He also held a grudge against police, deputy commissioner Gollschewski said on Tuesday,

"This is a person who was highly motivated and had a grievance against police," he said.

"We know that he had issues [with police]."

Commissioner Ian Stewart said both deaths, and the injury, were Maddison's fault.

"I squarely put everything that's happened in the last 24 hours in his court," Commissioner Stewart said.