Two motorcyclists have been killed in separate crashes over the weekend.
The first crashed happened in Scotsdale near Denmark around 8.30am on Saturday.
A 61-year-old man was riding with a group of other motorcyclists along Scotsdale Road when his bike left the road and crashed into a tree.
The man was thrown from his motorcycle and died at the scene.
Major Crash officers are also investigating another motorcycle crash that happened in Mundaring two hours later.
A 55-year-old man was riding along Phillips Road when a Toyota Hilux towing a box trailer drove into the path of the motorbike.
The rider was thrown from his bike and landed in the trailer.
He was rushed to St John of God Hospital in Midland where he later died.
Major Crash investigators are seeking witnesses to either crash to call Crimestoppers on 1800 333 000.
Baldivis Police on the lookout for reckless dirt bike riders
WATCH: Youths captured on CCTV stealing car in Golden Bay
Fire crews battle early morning blaze in Warnbro
Driver charged over alleged hit-and-run on Mandurah Terrace
More paramedics, ambulances to be stationed in Dawesville, Australind
Strict demersal fishing bans to come into force off WA coast to save species from extinction
Police call for witnesses to fatal Waroona crash
Teen injured in suspected hit-and-run in Mandurah