A radioactive cylinder went missing from a plant in Thailand. Officials still can't find it.

BANGKOK – Authorities in Thailand expanded their search Wednesday for a metal cylinder with radioactive contents that has gone missing from a power plant, warning the public that it poses a danger to health.

The 12-inch- cylinder containing the radioactive material Caesium-137 was noticed missing last Friday from a piece of machinery at a steam power plant in Prachinburi province, 60 miles east of Bangkok.

Ake Wongjinda, a public relations officer for the provincial government, said Wednesday that authorities have inspected locations such as junk shops, scrap metal yards and secondhand stores in Prachinburi and neighboring Chachoengsao province for the 55-pound-cylinder.

Health officials cautioned the public that prolonged direct contact with radioactive material can cause skin rashes, hair loss, canker sores, fatigue, and vomiting. They said short-term contact with Caesium-137 may not show immediate symptoms but could lead to a higher risk of cancer.

Fact check: False claim Thailand is banning Pfizer's COVID-19 vaccine after princess' health issues

Thailand: Captain of boys soccer team rescued from Thai cave in 2018 dies at English sports academy

Thongchai Keeratihuttayakorn, director-general of the Department of Medical Services, said Caesium-137 has similar physical characteristics to salt and can disperse easily if its container opened. He said it is used in devices such as ones measuring humidity or the velocity of liquids.

The cylinder was connected to a 56-foot-tall silo and used for measuring ash in the silo, said Permsuk Sutchaphiwat, secretary general of the Thailand's Office of Atoms for Peace agency.

Kittiphan Chitpentham, a representative of the National Power Supply Public Co., Ltd., the power station's owner, said it is not clear whether the cylinder had gone missing by accident. He said that the company would provide a $1,445 cash reward for anyone who can provide information about it. The company said it may have disappeared several weeks ago.

In 2000, illegally disposed cannisters containing the radioactive substance Cobalt-60 were found in a junkyard in Samut Prakarn, a suburb of Bangkok. At least five people were hospitalized after being exposed to radiation when the cannisters were opened by the scrapyard workers, unaware of the hazard. The cylinders were belived to have come from a medical X-ray machine.