Stephen Martin
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Derry bomb 'could have killed' say police

The police in Northern Ireland have described a bomb at the centre of a security alert in Londonderry as a "substantial viable device".

Police suspect that the bomb was planted by dissident republicans. Dozens of elderly residents were moved from a sheltered housing development due to the alert.

Chief Superintendent Stephen Martin said that if the bomb had gone off, it could have killed passers-by.