Horrified onlookers watched as a man repeatedly stabbed another man to death in a crowded Sydney shopping centre before finally leaving the knife lodged in the victim's chest.
The stabbing occurred on level four of Westfield Parramatta about 10.30am on Monday.
A witness, who did not want to be named, said he saw the attack from level 5.
He told AAP the attacker looked to be in his 40s and was taunting police officers at the scene.
"He kept plunging the knife in his chest, in and out, and paced up and down the shopping centre screaming at police," he said, adding that the man was stabbed three to four times.
"He taunted the police, saying 'what are you scared of?'"
The man eventually left the knife in the man's chest before police moved in to arrest him.
The witness said the knife looked to be about 30cm long and the ordeal lasted about 20 minutes.
"Everyone was very scared and begging for somebody to stop the attack," he said.
"There was blood everywhere."
Emergency services arrived to find a body of a man inside the shopping centre, police say.
A man has been arrested and taken to Parramatta police station where he is currently assisting with inquiries, police say.
Witnesses say several police Tasered the shirtless man, who had a large tattoo on his back, according to Macquarie Radio.
Shops in the busy Westfield centre near the stabbing were forced into lockdown, while the rest of the centre is still open.
The centre was busy with shoppers due to the NSW school holidays.
A crime scene has been established.
Myer and about 30 other stores are closed due to the fatal stabbing, a Westfield spokeswoman told AAP.
Level four and a part of level five are closed while police investigate the stabbing she said.
Counselling services are being provided by Westfield for employees, retailers and customers.
She said Westfield will be working with police to help with their investigation.
