By Paulina Vidal and Danuta Kozaki, ABC News
Six people have been killed in a knife attack at Westfield Bondi Junction shopping centre in Sydney's east on Saturday afternoon, NSW Police say.
Five of the victims died at the scene and the sixth died from their injuries in hospital, NSW Police said.
Nine people, including a small child, were stabbed by a man in the centre and some are in a critical condition.
The offender was shot dead at the scene by a police officer.
NSW Police Assistant Commissioner Anthony Cooke said authorities believe the man acted alone and there was no ongoing threat.
Assistant Commissioner Cooke said he did not have further information about the man's identity.
He said there was no indication of the offender's motive but police had not ruled anything out.
They said the man was in the shopping centre around 3pm before leaving and then returned around 20 minutes later with a knife.
A police inspector, who was nearby, was directed towards the man by witnesses, and she shot him dead after the offender confronted her.
"She confronted the offender, who had moved by this stage to level five, as she continued to walk quickly behind him to catch up with him. He turned to face her, raised a knife," Cooke said.
"She discharged a firearm and that person is now deceased."
A NSW Ambulance spokesperson said those injured had been taken to a number of hospitals across Sydney.
The baby had been taken to Sydney Children's Hospital at Randwick, another victim was taken to St George Hospital and another to Royal North Shore Hospital.
Three people were taken to Darlinghurst's St Vincent's Hospital, while another two are at Royal Prince Alfred in Camperdown.
Federal police join response to attack
A large number of emergency vehicles and personnel arrived at the scene after receiving triple-0 calls.
Armed police could also be seen conducting a search of the rooftop car park.
Commissioner Reece Kershaw said the Australian Federal Police would support NSW Police in the investigation of the attack.
"The AFP has deployed AFP members to the crime scene and we've offered our full specialist capabilities such as digital forensics," he said.
"It is too early to determine a motive and it would be unhelpful to speculate."
Kershaw said he had also spoken to the NSW police commissioner and the director-general of ASIO.
NSW Premier Chris Minns, who was on leave, will return to Sydney.
"I want to thank NSW Police, emergency services and first responders and the community for their bravery in the face of this shocking incident," he said.
Prime Minister Anthony Albanese said the attack was "beyond words or understanding".
"Australians will be shocked this evening," Albanese said.
"This was a horrific act of violence, indiscriminately targeted at innocent people going about an ordinary Saturday doing their shopping tonight."
Witnesses describe 'horrific experience'
ABC sound engineer Roi Huberman said he was inside a shop when he heard gunshots.
"And suddenly we heard a shot or maybe two shots and we didn't know what to do," he said.
"Then the very capable person in the store took us to the back where it can be locked.
"She then locked the store and then she then let us through the back and now we are out."
Shopper Adriana was with her two daughters at a beauty store when they heard gunshots.
"All of a sudden the front doors were closed and in a matter of seconds we heard some gunshots and got sent to the storage room at the back of the shop. There were about 30 or 40 people there," she said.
"Everyone was screaming, crying, trying to call their relatives. It was an horrific experience.
"There was a lot of screaming and people just screaming: 'Get out, get out, get out of the shopping centre.'"
This story was originally published by the ABC.