A motorbike rider has been seriously hurt in a crash that closed a busy intersection.

The 29-year-old man was injured when his black Yamaha and a silver Honda Civic collided at Southern River Rd and Gay St in Southern River, in Perth’s east, just after 6pm on Wednesday.

WATCH THE VIDEO ABOVE: Motorcycle rider injured in Southern River crash.

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St John WA paramedics took the man to Royal Perth Hospital with serious injuries.

The sedan driver, a 23-year-old woman, was not injured.

Major Crash investigators have appealed for witnesses as they investigate.

Anyone with information should contact Crime Stoppers.