Paramedics rushed to a home in Wanniassa to help a man after witnesses to an alleged altercation called triple-0.
ACT Policing arrived with ACT Ambulance at a home on Ashley Street about 5pm Wednesday.
A police spokesperson they found a man who had been victim to a "serious attack" and had to be taken to the emergency room with significant injuries.
The spokesperson also said the offender fled the scene before police arrived and an investigation to identify them was under way.
"Police spoke to witnesses at the scene but are appealing for anyone with any further information to come forward," she said.
She added anyone with CCTV or dash cam footage from specific streets, between 4pm and 5.30pm on September 4, should also contact police.
These include Ashley Drive, Michaelis Court, Comrie Street, Sternberg Crescent and McBryde Crescent.
The spokesperson believed the offender travelled through the areas before and after attacking the victim.
Anyone who may have witnessed the incident was urged to contact Crime Stoppers on 1800 333 000, or on the Crime Stoppers ACT website. They were asked to quote reference number 7842338. Police said information could be provided anonymously.
