Police hold concerns for the safety of five people, including a child, missing between Kalgoorlie and the remote community of Tjuntjuntjara for four days.
An air search for the group — four adults and an eight-year-old boy — is underway.
Heavy rainfall in the area has led to road closures and difficult driving conditions. The community has been cut off by floodwaters for the past fortnight.
It is feared the group's vehicle, a green Hyundai Excel, may have become bogged.
The adults are Rex Mitchell, Janice Stevens and Shonna Jamieson — all in their 40s — and Bruce Stevens, aged 24.
It is understood that the group left Kalgoorlie sometime on Tuesday but it is not known if they have food or water.
Tjuntjuntjara is 550 kilometres east of Kalgoorlie in WA's Goldfields region.
A search plane with a Department of Fire and Emergency Services observer on board has left Kalgoorlie to conduct a search, and nearby pastoral stations have been advised.
