Emergency crews on the hunt for a pea-sized radioactive capsule along a 870-mile/1,400-kilometre route in Western Australia found the capsule after the tiny device went missing while being transported from Rio Tinto’s Gudai-Darri mine in the Kimberley region.

The capsule was found just outside Newman, in the Pilbara region of Western Australia. A serial number enabled them to verify they had found the right capsule, which is 6 mm in diameter and 8 mm long.

According to a BBC report, the capsule contained Caesium-137, which can cause serious illness to anyone who comes into contact with it, including burns, skin damage or radiation sickness.

BBC noted that it left the mine site on 12 January and an inspection of the broken gauge was performed on 25 January.

Special equipment for detecting radiation was deployed to look for the small component, with technology attached to patrol vehicles that scanned the route in both directions.

Mining giant Rio Tinto apologised for losing the device and said it was undertaking an internal investigation into how the potentially lethal and radioactive substance, which is commonly used within gauges in mining operations, was lost.