(CNN) -- Security forces in Afghanistan seized 11 tons of ammonium nitrate, the material used to make improvised explosive devices, NATO's International Security Assistance Force said on Wednesday.
The forces, working with NATO-led troops, found the material during a Monday night operation in Kabul.
"Police surrounded a compound housing several insurgents. After ensuring all residents exited safely and arresting the insurgents, police found the very large cache of ammonium nitrate in the compound," ISAF said in a press release.
ISAF said the find eliminated more than 500 potential IEDs, a much-used insurgent weapon.
"IEDs cause the vast majority of civilian and military casualties in Afghanistan. Removing this much ammonium nitrate, which is the primary ingredient in homemade explosives, could save countless lives," said ISAF Joint Command spokeswoman Navy Capt. Jane Campbell.
IED incidents increased by 94 percent within the first four months of 2010 compared to the same period in 2009, according to U.N. figures cited by ISAF.
In Kandahar province on Tuesday, authorities seized 70 kilograms of opium in an operation disrupting a network that sold drugs to finance the Taliban insurgency.