A ten-man MI5 team followed the ringleader of the 21/7 bombers on the night he left Britain for terrorist training in Pakistan, The Times has learnt.

The Security Service was also alerted when Muktar Said Ibrahim returned to Britain three months later, but allowed him to enter the country unhindered.

Ibrahim, who tried to blow up a No 26 bus on July 21, 2005, will be sentenced with his three accomplices – Yassin Omar, Hussein Osman and Ramzi Mohammed – at Woolwich Crown Court today for conspiracy to murder.

The jury in the six-month-long trial was discharged yesterday after failing to reach verdicts on two other defendants.

‘Items sent as earthquake aid’

Hidden among clothing were goods selected and purchased to support the activities of terrorists, a court was told

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As new details emerge of apparent security failures that left Ibrahim free to carry out the attacks, there are growing demands for an explanation from the authorities.

Counter-terrorist sources have told The Times that Ibrahim was driven to Heathrow on December 11, 2004, by an Iraqi man who was a high-priority terrorist suspect. Their car was being followed.

The man, Rauf Mohammed, has been named in Home Office documents as being “actively engaged” in providing support to the insurgency in Iraq.

Ibrahim, 29, met the Iraqi through an East London mosque run by an ultra-orthodox Islamic sect and his association with Rauf Mohammed was the clearest indication that he was being turned from a street-corner activist into a possible terrorist threat.

The connection with Rauf Mohammed led to Ibrahim and his two travelling companions – who later died fighting in Iraq – being questioned at the airport by Special Branch.

While they were being interviewed, Rauf Mohammed was tailed as he drove back into London. In evidence given at his subsequent trial, the surveillance officers reported that he spotted them, abandoned his car and spent several hours trying to shake them off using practised counter-surveillance techniques. The Iraqi was later subjected to a deportation attempt, charged, tried and acquitted of terrorist offences.

Despite his links with this prominent terrorist suspect, Ibrahim was not stopped or questioned when he returned to Heathrow on March 8, 2005, after being trained to make explosives and groomed by al-Qaeda to be a suicide bomber.

Security sources have confirmed that they were alerted to Ibrahim’s return to the country but it seems he was not subjected to round-the-clock surveillance. One security source said: “He was regarded as a low-key follow-up. He wasn’t forgotten about, but the intelligence on him was not as worrying as it was on a whole host of others who were being watched at full tilt.”

If there was any form of monitoring or intelligence-gathering, it missed that Ibrahim was recruiting a cell of suicide bombers and making bulk purchases of hydrogen peroxide to manufacture bombs.

After the July 21 failed bomb plot, MI5 feared that Britain was to be the target of a pattern of repeated terrorist attacks, one every two weeks, security sources told The Times.

So alarmed were the security authorities that other home-grown Islamic terrorists were about to launch further attacks in the summer of 2005 that the official threat level was kept artificially at “critical” – the highest of all – even though there was no specific intelligence of an imminent strike.

Deputy Assistant Commissioner Peter Clarke, head of Scotland Yard’s Counter Terrorism Command, said that the four men convicted of the 21/7 attacks had told “ridiculous” lies in an attempt to evade justice.

“These men obviously set out to replicate the horrors that had been inflicted on Londoners on July 7, 2005,” Mr Clarke said. “But this was no spur-of-the-moment plan. It had been hatched over several months. They failed to set off their bombs – not through want of trying.

“Despite the carnage of July 7, on July 21 the public responded courageously, and without thought for their own safety.” He added: “These men are dedicated terrorists who no longer pose a danger to the public.”

Ibrahim will be sentenced along with Omar, 26, the Warren Street bomber, Osman, 28, the Shepherds Bush bomber, and Mohammed, 25, the Oval bomber.

The Crown Prosecution Service will announce today whether it wishes to pursue a retrial of the charges against Manfo Kwaku Asiedu, 34, the alleged fifth bomber, and Adel Yahya, 24, who allegedly purchased hydrogen peroxide but was not in the country when the attacks took place.

— Muktar Said Ibrahim was given British citizenship a year before the 21/7 attacks. He had initially been given sanctuary in 1990, aged 12, and was given exceptional leave to remain for four years.

He was convicted as a juvenile in 1993 of indecent assault. In 1995 he was sentenced to three years in prison after he knocked a 77-year-old woman to the ground and stole her handbag. Later he was given a two-year sentence for robbery and attempted robbery.

In 2000 Ibrahim was given indefinite leave to remain in the country. In 2004 he applied for and was given citizenship, even though the Home Office was aware of his criminal record

The warning signs

May 04 Muktar Said Ibrahim is photographed by police at a training camp in the Lake District; Yassin Hassan Omar, Hussein Osman and Ramzi Mohammed are also present

Aug 04 Police photograph Ibrahim during a disturbance at the Finsbury Park mosque in North London

Sept 04 Ibrahim is given a British passport despite having a criminal record

Oct 04 He is arrested at extremist bookstall in Oxford Street, London; charged with public order offence

Dec 04 Special Branch officers question Ibrahim as he is en route to Pakistan

Feb 05 A warrant is issued for Ibrahim’s arrest over the Oxford Street charges

March 05 Ibrahim returns to Britain from Pakistan

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