A man has had his jaw broken in two places following the incident.
Mandurah Detectives are investigating an assault in Dawesville, which left a 32-year-old man with a broken jaw.
On Tuesday around 9.30am it's alleged the victim became involved in an argument with a teenage boy at the Dawsville Bypass service station.
It's further alleged as the victim bent down the youth struck him on the jaw with a closed fist. The boy then fled the scene, running in front of a truck travelling on Dawesville Bypass and was almost hit.
The man required treatment for a broken jaw and a number of dislodged teeth.
Mandurah Detectives wish to speak to anyone who witnessed the assault, in particular two people who were walking on Dawesville Bypass at the time.
Anyone with information are urged to call Crime Stoppers on 1300 333 000 or online at www.crimestopperwa.com.au
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