A seven inch radioactive rod containing americium-241/beryllium used in association with hydraulic fracturing was presumably stolen on Sept. 11 from a locked storage facility. The padlock on the storage facility was missing along with the rod. Halliburton called off a search of the mine it was last used at 3am yesterday morning in order to inform the National Regulatory Commission. They plan a renewed search with more advanced equipment.
Although, not reportedly dangerous to an individual who has the sealed container in their possession for less than a few hours, the risk to the public is unknown were it to land in the hands of skilled handlers.
Source: http://www.bloomberg.com/news/2012-09-13/halliburton-hunting-for-missing-radioactive-probe-in-west-texas.html