Gunman allegedly killed neighbour as she sat in car with two kids

Footage has emerged of the moment police arrested a 31-year-old man accused of killing a woman as she sat in her car with two young children.

Ryan Geoffrey Cole was apprehended outside a service station after police had locked down nearby streets as they searched for him

It's alleged Cole shot the woman, a 34-year-old mother who police say he didn't even know, as she sat in her car with two children, aged 11 and 12, parked at a home on Robb Place in South Mackay yesterday afternoon.

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Cole then allegedly also shot a 66-year-old man, who police said was coming to the aid of the woman as the two children ran for help.

The alleged gunman faced court today charged with one count each of murder and attempted murder.

Police said Cole had been a previous licensed firearms owner and they were investigating reports he had owned up to 12 guns.

Detective Acting Superintendent Emma Novosel said Cole was the next-door neighbour of the victim and investigators were still trying to figure out a motive.

"Multiple crime scenes have been established and investigations are ongoing," she said.

The alleged gunman had previous interaction with police, but that had been "very minimal".

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Novosel said the man allegedly used a revolver-type pistol and fired one shot at each victim.

The woman was about to take the two children to a sporting activity when the alleged shooting happened.

The children managed to flee the scene and ran to the house of the 66-year-old man who was subsequently shot.

Novosel praised the courage of the children.

"It's obviously a tragic incident where these young girls have witnessed a violent death ... they were incredibly brave," she said.

She said the 66-year-old man had spoken with detectives from hospital where he has undergone surgery with wounds to his hand and sternum.

The accused gunman left the scene in his silver Mitsubishi Triton before police arrived.

Police locked down several streets for hours as they searched for the alleged gunman.

Officers tracked the car to a service station along the Bruce Highway near Hilton Street, where Cole was arrested.

The neighbourhood lockdown was lifted about 10.30pm.

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