Updated at 9.55pm

AUSTRIAN POLICE SAID at least three people were injured in a knife attack this evening on the streets of Vienna, with the attacker possibly injuring a fourth nearby.

Vienna police said the attack happened at about 7.45pm (6.45pm Irish time) on Praterstrasse in the heart of Vienna.

“According to eyewitnesses a man has attacked three persons – a man, his wife and their adult daughter,” police spokesman Patrick Maierhofer told The Associated Press.

“The three persons suffered heavy to life-threatening injuries and are currently in a hospital.”

A fourth person was attacked with a knife nearby shortly afterwards.

“A link [between the attacks] is part of ongoing investigations,” police said.

An officer blocks a street where police are on the hunt for the attacker Source: Ronald Zak via AP

Witness Silvia Franke said she was about 100 metres away when the incident happened.

“I saw how someone in the middle of the street was screaming and shouting — I thought he was beating his dog judging from his hand movements,” she said.

“And in reality, he was stabbing this man.”

“He could have stabbed me as well had I been there by chance,” Franke said.

“He had lost all control.”

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