Authorities in Western Australia say they are looking for a missing radioactive capsule.
The Department of Fire and Emergency Services said the capsule containing radioactive material was lost during transportation from north of Newman to Perth's northeastern suburbs.
Exposure to the material, used in gauges in mining, could cause radiation burns or radiation sickness, the department said.
The small silver capsule measures 6 mm in diameter and is 8 mm tall.
Workers are searching the Great Northern Highway for the capsule.
Motorists have been urged to check their vehicles' tires to see if the capsule has become lodged in the treads.
People, however, have been warned to stay away from the capsule if they see it because it contains radioactive material.