A 22-year-old man from Warnbro died after losing control of his motorcycle on the Mitchell Freeway where he was riding alongside his brother.
The crash happened at about 5:40am on Saturday when the man was riding a Hyosung motorbike south on the freeway in West Perth.
His 25-year-old brother was riding a separate bike and suffered minor injuries in the crash.
Witnesses told Seven News the older brother desperately tried to save his younger brother.
Both were taken to Royal Perth Hospital but the 22-year-old man died soon after.
Anyone who may have witnessed the crash is asked to call Crime Stoppers on 1800 333 000 or make a report online at www.crimestopperswa.com.au
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