Mining giant Rio Tinto Group has lost a “highly radioactive” capsule somewhere along a 1,400-kilometre highway that stretches across the Western Australian desert triggering a radiation alert in the country.

According to local media reports, the radioactive material went missing on the highway between the town of Newman and the city of Perth and the authorities have launched a hunt to trace the capsule.

“As well as fully supporting the relevant authorities, we have launched our own investigation to understand how the capsule was lost in transit,” Rio Tinto’s Iron Ore chief executive Simon Trott said in a statement.

“We are taking this incident very seriously. We recognize this is clearly very concerning and are sorry for the alarm it has caused in the Western Australian community,” the statement added.

The mining giant and Western Australia’s government are attempting to find the widget, which is as much as 8 millimeters (0.3 inch) in length and contains a small amount of the radioactive isotope caesium-137. The casing contains a small quantity of radioactive Caesium-137, which could cause serious illness if touched.

While the risk to the general community is low, exposure to the substance could cause radiation burns or radiation sickness, Emergency Western Australia said on its website.

The widget was a component in a gauge used to measure the density of iron ore. Rio Tinto said the radioactive capsule was collected from the mine on Jan. 12 by a transport contractor, and was due to arrive at a radiation storage facility in Perth on Jan. 16. It was only discovered to be missing when its container was opened for inspection on Jan. 25.

The Western Australian government said when the package holding the device was inspected, it was found to have been “broken apart with one of the four mounting bolts missing and the source itself and all screws on the gauge also missing.”