Sydney CBD knife attacker tells police to 'shoot me in the face'

UPDATE 4PM

A young man has attempted to stab a number of people in Sydney's central business district with one woman rushed to hospital covered in blood.

NSW Police on Tuesday afternoon said a man was in custody after a woman was stabbed in a hotel. She's been taken to hospital in a stable condition with a stab wound to her back.

Witnesses have told AAP a young man armed with a 30-centimetre kitchen knife had been yelling religious statements.

Police say it's been reported he was yelling "Allahu Akbar".

Witness Zak Barry said he saw the man fall down on York Street "and as he's falling he dropped a kitchen knife".

Paul O'Shaughnessy, 37, said his brother Luke, 30, saw a man with a balaclava wielding a knife.

The pair chased the man and then managed to get a grip on him with the help of a third person.

"He's got blood all over him ... shouting religious statements," Mr O'Shaughnessy told reporters.

Video posted on Twitter shows the man yelled at police: "F***ing shoot me in the f***ing head" before he was wrestled to the ground by bystanders and a milk crate was placed over his head.

"A number of members of the public physically restrained the offender," Superintendent Gavin Wood said.

"I want to acknowledge those members of the public who got involved. They were significantly brave people."

Supt Wood said it appeared Tuesday's attack was unprovoked and the man had acted alone.

A caller to 2GB radio confirmed the young man had been tackled to the ground.

"He's definitely been detained ... he's been taken away," the caller, Tom, said.

The woman was taken out of the Hotel CBD and placed into an ambulance.

"So insane! A random dude just started stabbing people in the city right outside where we were having lunch," @JackHuddo said on Twitter.

An Uber driver said he saw people running away "and next thing I see this guy jumping over the car, he went over the bonnet, and went on top of the car".

"He had a little bit of blood on his shirt," the driver told 2GB.

NSW Police have set up a series of roadblocks in the area.

"A number of crime scenes have been established," a spokesperson said.

Supt Wood said there was no ongoing threat after the man's arrest.

  • Australian Associated Press

EARLIER

A man is in custody after allegedly stabbing a woman in Sydney's CBD this afternoon.

About 2pm, emergency services responded following reports a man was walking along York Street, Sydney, armed with a knife.

As police made their way to the location, there were multiple reports the man had stabbed someone near the corner of King and Clarence Streets.

Police and NSW Ambulance paramedics located a woman inside a hotel, who had a stab wound. She has been taken to hospital in a stable condition.

A short time later, members of the public detained the man before police attended and arrested him.

He has since been taken to Day Street Police Station.

Officers from Sydney City Police Area Command, and various specialist police, are conducting proactive patrols the area, but it is believed there is no further threat to public safety.

A number of crime scenes have been established and a number of road closures are in place, which is believed to have significant impact on traffic and public transport this afternoon.

  • NSW Police Media

EARLIER

Multiple police, fire and ambulance vehicles have raced to Sydney's central business district amid reports of a stabbing.

NSW Police said a "police operation" was underway near King and Clarence Streets in the city on Tuesday afternoon.

"Please avoid the area," the force said on Twitter.

Unconfirmed reports on Twitter suggest a man may have tried to randomly stab people on the street.

A caller to 2GB radio said a young man who had a knife had been tackled to the ground.

"He's definitely been detained ... he's been taken away," the caller, Tom, said.

  • with Australian Associated Press

Lifeline: 13 11 14 www.lifeline.org.au

MensLine Australia: 1300 78 99 79 www.mensline.org.au

Beyond Blue: 1300 224 636 www.beyondblue.org.au