According to the metropolitan police, mobile phone records analysed after the bombings on July 7, 2005, showed that calls were made from phone boxes in Rawalpindi to bomber Khan. Fifty-two people were killed in the bombs that hit three tube trains and a bus in London.
Detective Sergeat Mark Stuart said at the ongoing inquest that one of the calls was made on July 2, five days before the deadly bombings, and lasted six minutes.
Hugo Keith, counsel to the inquests, asked, "Did you assess that those calls therefore were probably connected to some guidance or some means of communicating information concerned with the manufacture of the bombs and then ultimately their detonation?"
Stuart replied, "Yes, I think they had to be." The BBC reported that many of the phone calls were made from different phone boxes within minutes of each other, which suggested that the caller had the intent to conceal his identity.
"I think these call boxes were actually in shops where there might be a number of people waiting to use them so he may have moved on for that reason," Stuart said.
The police believe Khan gave the Pakistan contacts the numbers for four phones, used solely in relation to the bombings plot. He never made any calls to Pakistan himself. The majority of the phone conversations took place between May and June 2005.
The inquests were told that the last call to Khan was recorded on the afternoon of July 7, when the attacks had been "brought to worldwide attention". Having examined each of the bombings in turn, the hearings have now shifted their focus to wider issues surrounding the attacks.
Keith suggested one possible question for examination was whether the authorities -- particularly the Security Service, MI5 -- might have done more to identify Khan and the threat he posed.
Prior to the 7/7 attacks, Khan had been spotted by authorities carrying out surveillance of suspected terrorist plotters but he was considered a peripheral figure and never identified.
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