Any unexploded devices would be valuable evidence for investigators to determine who was behind the bombing.
The unexploded bomb left crucial evidence intact that detectives used to trace Mr Shahzad.
Then there is the noise of bombs and shells, and dangers from unexploded ordnance.
The FSA will try to get the unexploded canister out of the country for testing, he said.
These banners once advertised a trade fair, but now lay wrapped around an unexploded, yard-long Israeli bomb.
The unexploded bomblets are a danger to residents, especially children who might pick them up, Amnesty says.
When pressed he said it was a piece of unexploded ordnance left over from the Vietnam War.
He was killed when he picked up unexploded artillery after leaving his checkpoint and walking into a field.
Military property contains a lot of unexploded ordnance and polluted groundwater, two of the trickiest types of contamination.
The United States maintains that most of the unexploded projectiles on Empire Range have been found and destroyed.
It would pay for locating, disarming and removing mines and other unexploded ordnance in the U.S. sector of Kuwait.
Electricians were shocked to find an unexploded World War II bomb at a former home of a war veteran.
Unconfirmed reports said two other unexploded devices were found near the end of the race but were safely defused.
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The debris and unexploded munitions clogging the river are causing severe economic disruption.
It may seem surprising that unexploded bombs remain undiscovered in Berlin and other German cities decades after World War II ended.
He recalled seeing stockpiles of explosively formed penetrators, as well as charges that had been recovered from unexploded American cluster bombs.
Last week, Syrian rebel spokesman Louay al Mokdad claimed opposition fighters had captured an unexploded canister from an alleged chemical weapons attack.
Many unexploded bombs dropped by Allied forces during World War II remain undiscovered in Berlin and other cities some seven decades later.
At least two unexploded devices were found in their house, police said.
In Syria, every time the government has used cluster munitions and other explosive weapons, a lethal legacy of unexploded ordnance is created.
Even without unexploded devices, investigators can still sift through the blast marks of the detonated devices to determine how the bombs were constructed.
He said federal investigators were examining the two unexploded devices which were found on the busy Jangli Maharaj Road area, where the blasts occurred.
The abandoned, unexploded ordnance, combined with oil from leaks or deliberately flooded trenches, has left a hazardous environment for rehabilitation workers to operate in.
In the south Israel's scattering of hundreds of thousands of unexploded cluster bomblets has hampered reconstruction, as well as farmers' access to their fields.
But in one of the driest Novembers on record, Rhine River levels have dropped dramatically, revealing an unusually large trove of unexploded bombs in its bed.
Iran invited a United Nations inspection team onto its territory to examine the victims, witness the damage, and study the unexploded chemical munitions fired from Iraq.
American, British and Dutch planes dropped more than 1, 500 cluster bombs on the province in three months, leaving an estimated 20, 000 unexploded bomblets on the ground.
Mr. Lenz added that as unexploded bombs grow older, they are becoming ever more unstable, and increasingly likely to explode, as the elements deteriorate their chemical detonators.
On a separate issue, the spokesman said that the rebels had secured what they believe is an unexploded chemical weapon deployed by the regime Monday in Idlib.
Any unexploded devices could provide a treasure trove of information such as fingerprints and indications of the bomb maker's design, said the former federal law enforcement official.
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