Melbourne attack: Police say suspect has mental illness

A man with mental health issues has been arrested over an horrific attack in Melbourne.

The 32-year-old appears to have deliberately driven an SUV into pedestrians at a busy intersection on Flinders St, injuring 19 people, on Thursday. Four are in hospital with critical injuries.

One of those hurt is a New Zealander, the Ministry of Foreign Affairs and Trade confirmed Friday morning, but Newshub understands the 43-year-old male has been released from hospital.

 The High Commission in Canberra has offered consular assistance.

"Due to privacy considerations we are unable to provide any further information."

Victoria Police Acting Chief Commissioner Shane Patton says while it's still early in the investigation, they don't think the man's attack is terror related.

"He is on a mental health plan and receiving treatment for a mental illness. We are working through those to clarify that," he told media.

The man however is known to police.

"He has historical assault matters. He is not currently on any bail or any corrections order," said Mr Patton. "He has a history of drug use as well as mental health issues."

Despite the police's statement, Victorian Premier Daniel Andrews called the attack a "horrific act, an evil act, an act of cowardice perpetrated against innocent bystanders".

"What has occurred on Flinders Street was an act of evil and act of cowardice at a time of year when people should be out celebrating and doing their Christmas shopping.

"What we have seen is a horrific, evil, act and one that will be condemned by all Victorians, but at the worst of times we have also seen extraordinary courage from Victorians."

A 24-year-old man who filmed the incident on his smartphone has also been arrested, but it's not known if he was involved.

"​At this time we don't have any evidence or intelligence to indicate a connection with terrorism," Mr Patton said.

The incident is being investigated by the homicide squad, major collision investigation unit and Counter Terrorism Command.