New Delhi, Sept. 9 -- Dr Umar Un Nabi, the bomber in last year's Red Fort terror attack used a "command mechanism" through a piezoelectric plate attached to his shoe to trigger the explosion, effectively making it a "foot or shoe" operated bomb, the National Investigation Agency (NIA) said in its charge sheet. The agency's discovery removes the ambiguity that the bomb may have gone off accidentally after Nabi panicked, and establishes that it was deliberately triggered at Red Fort, considered by the group as a symbol of the Indian state.

The federal agency filed a charge sheet in the bombing in May this year against 10 individuals but a Delhi court took cognizance of it only on August 29. HT has reviewed the document. Twelve people inclu...