A highly radioactive but tiny capsule has gone missing in Western Australia and has sent authorities on an urgent search.

The capsule contains a small quantity of radioactive Caesium-137 and can cause serious illness. The firm handling its transportation has issued an apology stating that it has launched its own investigation into the matter.

The capsule went missing during transit between the town of Newman and the city of Perth in mid-January. It was being transported to a mine site north of Newman. Authorities sent out a warning about the missing capsule last Friday.

According to the Department of Fire and Emergency Services (DFES), the capsule can cause burns and illnesses like cancer but cannot be weaponised.

"Our concern is that someone will pick it up, not knowing what it is. They may think it is something interesting and keep it, or keep it in their room, keep it in their car, or give it to someone," said Dr. Andrew Robertson, the state's chief health officer and chair of the Radiological Council, per BBC.

The Australian authorities have launched a massive operation to locate the capsule. Anyone who has seen the object has been asked to call the DFES and seek urgent medical assistance.

The DFES has also released details about what it looks like so no one touches it accidentally. The silver-coloured capsule is just 6mm (0.24 inches) in diameter and 8mm long.

External exposure to large amounts of Cs-137 can cause burns, acute radiation sickness, and even death, according to the US Centers for Disease Control and Prevention. It is used in small amounts within gauges in mining operations and in medical radiation therapy devices for treating cancer.

In 2017, a vehicle carrying an unknown quantity of radioactive material was stolen in Mexico. The pickup truck was transporting mobile industry radiography equipment containing Iridium-192.

That was not the first time radioactive materials were stolen in Mexico. There have been several similar incidents since 2013. A container with a radioactive substance used in industrial X-rays went missing in early 2016 but was later recovered.

Iridium-192 is a highly radioactive isotope of the element Iridium, which has widespread industrial applications and is used in the medical field. It is also one of the isotopes that loses its potency quickly.

Radioactive material
Representative image Getty