Midland County Sheriff Gary Painter says the rod went missing on September 11th.
A Halliburton crew used the rod at a southern Reeves County well site along TX 18 around 5 AM on September 11th, but it was retrieved and placed into a work truck.
The truck then drove down F.M. 1788, to a well site about 20 miles south of the Midland County-Upton County border.
Once at the second work site, Halliburton workers found out that the rod was missing.
Halliburton workers used Geiger counters to look for the missing rod, but they reported it missing around 8:45 AM on September 12th.
Several law enforcement agencies and the Texas Department of State Health Services are now looking for the radioactive rod.
D.S.H.S. is also requesting support from the 6th Civil Support Team -- a Texas National Guard unit based in Austin with specialized equipment that can be used to locate radioactive material.
The silver rod -- which is usually held in protective casing under lock and key -- is 7 " long and 1 " wide.
The rod has the words "Danger-Radioactive" and "Do Not Handle" -- along with a radiation warning symbol -- stamped in red on the side, .
The rod also has a brass bolt screwed into one end.
The rod contains Americium241/Beryllium (Am241 Be) -- which is radioactive.
While the rod is not dangerous when touched, it can cause radiation poisoning if it's held in bare hands or carried in a pocket for a long period of time (particularly for about 2 days).
Anyone who sees the rod should stay at least 25 feet away from it and not touch it.
Anyone who knows where the rod might be should call the Midland County Sheriff's Office at (432) 688-4600 or the nearest law enforcement agency.