The ATF is searching for over 1,100 pounds of ammonium nitrate stolen from companies in Colorado and California in recent days.

Ammonium nitrate, mixed with fuel oil, were the key ingredients in the Oklahoma City bomb back in 1995. By itslef, ammonium nitrate is used as fertilizer.

A nationwide alert was issued Monday by the Bureau of Alcohol, Tobacco, Firearms and Explosives after eight 50-pound bags of an ammonium nitrate-based explosive vanished from the Pike View Quarry near Colorado Springs.

The other theft, 700 pounds of an ammonium nitrate product, occurred Sunday or Monday from Tom C. Dyke Drilling and Blasting in Alpine, Calif., about 30 miles east of San Diego, authorities said. Thieves forced their way into a locked trailer and took 16 50-pound bags. Two of the bags have been found.

This sounds somewhat ominous:

Authorities had said the material stolen in Colorado was already mixed with fuel oil and had a strong diesel fuel odor.