“Their parents are also understandably immensely relieved,” he said.
“As I said earlier today, any incident of this nature where children are taken from a property is concerning for police and it’s certainly concerning for the broader community as well.
“The four in custody will be interviewed tonight and we’ll continue to work through to piece together exactly what has happened.”
Earlier on Monday, Detective Inspector Thomas said the mother was taken to hospital with serious injuries.
“We’re currently speaking with the mother of the two children, and also the father, and they are both co-operating with us and doing everything they can to assist us to locate the children,” he said. “They’re very distraught … ”
The mother told police she did not recognise the man who assaulted her, and that she did not let him into her home.
The armed assailant was described as having dark skin and was wearing a dark-coloured hoodie and a surgical mask.
Inspector Thomas said the children’s father, employed in the building industry, was at work when the home invasion took place.
He said investigators were working on the premise that it was not a random attack but an “isolated matter”, with no other crime reported in the area. The motive was unknown.
Anyone who sights the black Mercedes, registration BEQ 882, or the children was urged to contact triple zero immediately.
Nearby residents said they were unaware of what took place until the mother crawled out of the home.
Chloe Krakouer said she was driving past with her mother about 8.50am when she saw a woman lying on the driveway bound and gagged.
Ms Krakouer said a man appeared to be helping the woman and that police arrived seconds later.
“She was on the ground in the driveway. She looked hysterical,” Ms Krakouer said.
“We saw a lady on the nature strip and her mouth was bound, her hands were bound, her feet and everything …” she said.
“She was just screaming; there was a man with her helping her. We were concerned, wondering what was going on.”
Forensic crews spent hours at the scene, removing items in including a phone. Children’s toys and bikes could be seen strewn across the front yard of the white weatherboard home on Monday afternoon.
Police patrolled the nearby area in the hope of finding the children and the car.
Detectives were also asking anyone who was travelling in the Blackburn North area from 8am on Monday to check any dash-cam footage they might have for the car.
Anyone with other information is urged to contact Crime Stoppers on 1800 333 000 or visit crimestoppersvic.com.au.
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