Three crews arriving in the area found a meter had fallen on the youngster outside Bunbury Museum, who was rushed to the nearby Bunbury hospital by air ambulance.
The post read: "We would like to advise our community that the Bunbury Museum and Heritage Centre and Bunbury Visitor Centre are closed today and tomorrow.
A spokesperson for WorkSafe WA, the body responsible for public safety in Western Australia, said representatives have confirmed the boy was hit by a disused meter in a courtyard at the Bunbury Museum.
Representatives for the City of Bunbury followed with their own post outlining the closure, adding their thoughts were with the child and family "involved in the tragic incident this week".
Five-year-old toddler fighting for his life after parking machine crushing A five-year-old boy is fighting for his life in hospital following a horror accident involving a parking meter.