A crash involving a truck and two cars has caused significant peak-hour disruptions on a major WA highway.
Two men in their 70s were travelling in one of the cars when the crash happened at the Greenlands Road turnoff to Forrest Highway in West Pinjarra just before 6.30am on Wednesday.
St John Ambulance sent four crews to the scene and rushed one of the men to Peel Health Campus in Mandurah with non-life-threatening injuries.
Those in the other car did not require an ambulance, nor did the truck driver, a St John Ambulance spokesperson said.
Main Roads WA has closed the southbound lanes of Forrest Highway at Greenlands Road, with motorists urged to find an alternative route.
Lengthy delays are expected and it is unclear when the highway will reopen.
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