LOUISVILLE, Ky. (WDRB) -- The search is on for 90 pounds of missing explosives stolen from a Jeffersonville, Indiana, construction site. 

Federal agents are now asking for the public's help -- but the material may be hard to find.

The busted lock on the back of a trailer shows where someone swiped nine 10-pound bags of ammonium nitrate from a construction site at River Ridge. 

"It's a blasting agent," said Nancy Allen, vice president of HTA Enterprises. "It takes a high explosive to set it off."

The explosives belong to HTA Enterprises: the same Louisville company that did the blasting and drilling on the East End Bridge project. 

Allen spoke to us by phone. 

"We've been in River Ridge since they started developing," she said. "We blast the rock prior to the excavation process, so they can get down to the grade they need to do the projects.

At River Ridge, you can see where crews used explosives to blast and pull up the ground as a precursor to laying utilities lines. 

"It's just an unfortunate incident that occurred on-site here," said Mark Hildenbrand, project manager at River Ridge.

River Ridge is in the midst of a development boom. Amazon is the most notable tenant in the industrial park, though you constantly see construction on the 6-acre site. 

"Right now we've got about five or six different contractors working for us," Hildenbrand said.

Hildenbrand touts $15 million in ongoing projects, but admits there have been some issues with theft. 

"It's mainly minor theft on some of the old facilities left after the ammunition plant was decommissioned, and what we're doing to combat that is demolish the buildings that have been left over," he said.

The explosives disappeared sometime between June 8 at 4 p.m. and June 9 at 6:30 a.m., not far from one of those ammunition sites. There is no word on why Bureau of Alcohol, Tobacco, Firearms and Explosives agents waited so long to ask for the public's help. 

Ammonium nitrate is a fertilizer, but when it's combined with fuel it puts the boom in dynamite. By itself it's not considered as dangerous, but no one wants it in the wrong hands. 

"It's what we do and I just hate it because it's bad for the industry," Allen said.

The government put up a $5,000 reward for tips leading to the missing explosives. Anyone with information is asked to contact the ATF at 1-888-ATF-TIPS (1-888-283-8477), by email at ATFTips@atf.gov or online at www.atf.gov/contact/atftips. Tips will remain confidential.

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