Officials Tuesday cautioned that this type of bomb could have been made by any number of groups or individuals.

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Two pipe bomb type devices were later recovered from Clandeboye Drive and Cluan Place.

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"Remicade is considered by many physicians to be a nuclear-bomb-type treatment, " says Walsh at Jefferies.

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Donal O'Sullivan, general manager of Haggerston Castle, said investigations were continuing to determine exactly why type of shell the bomb was.

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The attorney general said there was little evidence of the type of burn marks typical in a bomb blast.

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In a 2011 ruling, Duffy wrote that while Yousef was awaiting trial, he had been trying to collect urea -- a component of urine -- and a type of watch that had been used in a detonator in the airline bomb plot.

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