A MUSLIM police officer stopped from guarding the Prime Minister over fears his Swindon mosque was infiltrated by Al Qaeda has been barred from attending his own employment tribunal.

Firearms officer PC Amjad Farooq, 40, worked for the Diplomatic Protection Group guarding senior dignitaries, which included Prime Minister Tony Blair.

But the former Wiltshire Police firearms officer was transferred from the Metropolitan Police's section on the advice of MI5 after a vetting check uncovered fears that Al Qaeda had a foothold at the Jamia Masjid Mosque, in Broad Street, Swindon.

Now it has emerged that Mr Farooq's employment tribunal, brought against the Metropolitan Police on racial and religious discrimination grounds, will be heard in secret because of national security.

Central London Employment Tribunal opened the case on Thursday with speeches from both sides. It was then expected to hear evidence about the work of intelligence services agents.

During the case not even PC Farooq or his legal team will be allowed in court for long periods - instead a "special advocate" will take their place.

The Advertiser first reported PC Farooq's case in November 2006. We said the Broad Street mosque rubbished claims it was linked to terrorist groups, and the imam MI5 was reported to be concerned about had left the mosque years before.

The tribunal will be told PC Farooq was recruited to the Metropolitan Police's specialist unit in 2003 in a drive to recruit more black and ethnic minority officers.

Before he could carry a gun he had to go through a full counter-terrorism clearance.

But, it is claimed that in December 2003 he was told he had failed his CTC and he was transferred to a lesser post.

A senior officer told him that the Met had evidence to justify the refusal of the CTC.

Scotland Yard has refused to say why PC Farooq was barred from working in the DPG but says it was justified in doing so.

It has been claimed that the refusal followed MI5 intelligence that two of PC Farooq's sons, then aged nine and 11, went to Broad Street mosque where they were taught by an imam linked to Pakistan terror group Sipah-e-Sahaba.

The group is believed to be a formal part of the Al Qaeda network and outlawed in Pakistan.

PC Farooq, who now lives in Gloucester, denies links to extremists and is seeking £25,000 in damages.

A worshipper at the mosque, who did not want to be named, said: "There was an imam here who was forced to step down because the other imams did not approve of his association with Sipah-e-Sahaba.

"But the imam did not have strong connections with Sipah and certainly had nothing to do with politics or violence, he just subscribed to some of their beliefs.

"As for Amjad, he had nothing to do with them, and nor does anyone else here at the mosque.

"We are all professionals or businessmen. Fitting in prayer five times a day is hard enough without having time to get involved in politics or extremism."

PC Farooq's solicitor Lawrence Davies said: "This is the first employment tribunal where the public and press have been barred on grounds of national security.

"We challenged the tribunal's decision but the Employment Appeal Tribunal held that it did not breach Mr Farooq's right to a fair trial."

The outcome of the tribunal will be known when the panel publishes its judgment some time in the summer but it may not disclose much of the evidence heard on which its ruling was based.