The Department of Homeland Security announced it plans to regulate the sale of ammonium nitrate, 16 years after the fertilizer was used to kill 168 people in the 1995 bombing of a federal office building in Oklahoma City.
Under the proposed regulations, anyone who buys, sells or transfers 25 pounds of the chemical must apply to register with the department. Ammonium nitrate facilities must also keep records of sales or transfers of the chemical for at least two years after each transaction.
