Scandinavian fighting for life after one punch attack in Perth

A man has suffered a serious brain injury in an unprovoked one punch attack in Perth.

Police say the 44-year-old was knocked out while walking through the Cultural Centre in Northbridge with a female relative around 5am on Easter Sunday.

The Scandinavian needed brain surgery after falling backwards and hitting the ground.

He is currently in intensive care at Royal Perth Hospital.

Detectives said the offender left the Cultural Centre with friends and walked towards Perth train station.

He is described as fair skinned with dark collar length hair.

He was wearing dark ripped jeans, a black T-shirt with "diamond" written on it, white sneakers, a black cap and a gold chain.

Police are urging anyone who saw him, his friends, or the attack to get in touch.

A Brazilian national was knocked unconscious outside an Irish pub in the city, and Italian waitress Stella Trevisani was stabbed as she walked home from work in East Perth.