It was two o'clock in the afternoon local time when the police received the first calls about a man walking around central Sydney, armed with a large knife and with blood on his clothes. He stabbed a woman outside a hotel and tried to attack several other people. The condition is described as stable for the injured woman.

Mobile footage from the incident shows how many are fleeing in panic, while several other people are chasing the man. He is overpowered and held with the help of chairs and a plastic back, before the police arrive.

At a press conference, the police praised the people who stopped the man.

"They are the biggest of heroes," says Mick Fuller, New South Wales Police Chief.

He tells a radio channel in Sydney that several deaths would probably have been required had the men not shown great courage and stopped the knife man.

Link to the death victim

After removing the arrested one, a witness informs the police that he heard screams from a nearby building. In an apartment where the police find a dead woman. Police say there appears to be some sort of link between the death victim and the suspected perpetrator.

"All the information indicates that the events are related," said Police Commissioner Mick Fuller.

Believe to be lone wolf

The detainee has previously been diagnosed with mental illness, as has been known by the police, writes The Guardian. Police also believe the man appears to have acted alone.

In Sydney mobile films, the man is heard shouting "Allahu akbar" and when he was arrested he carried on a USB stick with information about terrorist attacks, including the mosque attacks in New Zealand, and extreme ideologies, according to police.

But he has no known terrorist links and the deed is not considered a terrorist offense at the moment, says Mick Fuller.

Suspected of murder and attempted murder

"Our thoughts go to those affected by the violent attack," Australian Prime Minister Scott Morrison wrote on Twitter.

The 21-year-old man has been hospitalized for minor injuries. He is expected to be formally charged with murder and attempted murder after initial interrogation with police, writes the Sydney Morning Herald.