A nuclear reactor in Norway leaked a small amount of radioactive iodine, according to Norway's Radiation Protection Authority.
Iodine is used to treat thyroid cancer, but exposes to large doses can increase the risk of leukemia.
The leak started Monday afternoon about 70 miles east of the capital, Oslo, but was not reported until Tuesday, USA Today reports. The leak has since been contained and is not expected to be dangerous to workers' health.
We'll update this as soon as we know more.