New Delhi, Nov. 10 -- A year after a group of doctors associated with al-Qaeda in the Indian Subcontinent (AQIS) carried out a high-intensity vehicle-borne bomb blast near Delhi's Red Fort, the National Investigation Agency (NIA) has completed its investigation into the attack, with only two key suspects remaining to be traced, people familiar with the development said on Monday. The federal anti-terror probe agency recently concluded its arguments on the framing of charges against all 13 charge-sheeted accused before a special court in Delhi, detailing the conspiracy and the technical and physical evidence gathered against them. The defence counsels are likely to begin their arguments from November 16, the people said. "A foreign handler, Dr Ukasha, whose exact location is not known, and an absconding key local suspect, Muzafar Ahmad alias Faraz, are the only ones left to be traced. Other than that, the investigation in the case is more or less complete. The court has been informed that no further investigation is required in the blast," one of the people said. The NIA has filed two charge sheets in the case: the first in May against 10 accused, including Nabi, and a supplementary charge sheet in June against three more suspects. According to details of the charge sheet reported by HT in September, Nabi used a "command mechanism" involving a piezoelectric plate attached to his shoe to trigger the explosion, effectively making it a "foot or shoe"-operated bomb. The probe also revealed that the group chose the Red Fort as its target because it considered the monument symbolic of the Indian state. "The NIA has produced material and technical evidence ... which will lead to conviction," the person said....