“It doesn’t get any worse.”
Superintendent Humphrey said it’s believed the killer fled along Queen Street and urged any witnesses to come forward.
“You may have had dashcam footage or you may have just witnessed someone in the area running or acting suspiciously,” he said.
“I am convinced it is a targeted attack, for what purpose I do not know.
“I want to assure the Stockton community, though, the likelihood of a recurrence of this offence is very unlikely.”
Newcastle police officers established a crime scene at the home.
Queen Street resident Geoff Dunn, who lives across the road from where Ms Klimovitch was killed, said he heard a gunshot on Wednesday night.
“I thought my son knocked something over in his bedroom,” he said.
“I realised it was something else when I heard the police.”
Mr Dunn said the street was still blocked off by police on Thursday morning.
“It’s a block of flats there and people sort of come and go, I didn’t know her personally,” he said.
“It’s not a very nice thing to happen. We’re a dead-end street here. We don’t always have too much happening.”
Detectives formed Strike Force Backhouse to investigate.
Residents reported on social media seeing up to 12 police cars and multiple ambulances racing down the street and a helicopter overhead after the shooting.
Police have urged anyone who has CCTV or dashcam footage from the area at the time of the shooting to contact Newcastle Police or Crime Stoppers on 1800 333 000.
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