AN electronic tracking device of the type used by police to monitor suspected terrorists was recovered from a car belonging to the leader of the London suicide bombers in the days following July 7, a senior security official has claimed.

The device is thought to have been placed inside Mohammad Sidique Khan’s car by Special Branch officers in a surveillance operation aimed at Islamic extremists in West Yorkshire.

The suggestion that police were monitoring Khan before the 7/7 attacks will fuel claims that the authorities may have missed intelligence that could have foiled the terrorists.

::MMPU::MI5 has already been criticised by victims’ relatives and opposition MPs for allegedly failing to act on clues about Khan’s activities before the attacks, in which 52 people and the four bombers died.

With the first anniversary of the bombings next week, the claim has reignited calls for a full public inquiry into what the security services and the police knew about the terrorists before the attacks.

Yesterday Martin Gilbertson, a computer expert who had worked in an Islamic bookshop with the bombers, claimed that he had tipped off police in Holbeck, West Yorkshire, about “suspicious activities” by Khan and Shehzad Tanweer, another of the July 7 bombers.

Gilbertson told The Guardian that in October 2003 — almost two years before the attacks — he had posted a package of incriminating material to West Yorkshire police headquarters and asked anti-terrorism officers to contact him. He said it showed that Khan and Tanweer were linked to extremist “holy war” websites. However, Gilbertson said he had received no response.

After the July 7 attacks, Khan was identified by a credit card and other items found near his body within two days of the blasts. A silver Honda Accord was later removed from his home in Dewsbury, near Leeds.

Asked yesterday to respond to the claims that a tracking device had been in Khan’s car, a spokesman for West Yorkshire police said it was a matter for the Metropolitan police, which is leading the inquiry into the bombings.

The Met said yesterday that it had a policy of never commenting on questions about whether there was any intelligence or surveillance on any of the bombers before July 7.

Yesterday a government official said he was unaware of the police device. He insisted that there had been no attempt to cover up the truth about any potential intelligence failings.

However, Patrick Mercer, the Tory spokesman on homeland security, said: “If this is true, it is yet another indication that the authorities suspected that Khan was up to his neck in terrorist activity. This underlies why we need an independent inquiry.”

On Friday, West Yorkshire police said they did not have any records to show whether they had received a tip-off from Gilbertson; whether, if it had been received, it had been discounted, “or whether it was acted upon in some way”.

Yesterday the force revised its statement, saying: “Whenever we receive information that could potentially be intelligence on crime or terrorism matters, this information is carefully considered and analysed.”

A report by the parliamentary intelligence and security committee revealed Khan had come to the attention of MI5 in the two years before July 7.

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