Police were tonight continuing to hold 14 men arrested as part of an anti-terror investigation that has seen officers spend another day searching an Islamic school.
Detectives appear to be focusing on the education establishment in West Sussex but are also examining residential properties – running into double figures - across London following the arrests overnight on Friday.
It has emerged radical Islamic cleric Abu Hamza – jailed for seven years in February after being convicted of a string of race hate and terror charges - stayed at the school for a short period but was asked by staff to leave.
The arrested men, aged from 17 to 48 years, were detained in the capital under the Terrorism Act 2000 after months of surveillance involving Scotland Yard’s Anti-Terrorist branch and MI5.
Some of the men, who are thought to be mainly young British Muslims of Pakistani origin, were arrested at a Chinese restaurant in the Borough area of the city.
A Scotland Yard spokesman said the men had been held on suspicion of the commission, preparation or instigation of acts of terrorism.
He added that the arrests were not linked to the recent alleged plot to blow up transatlantic airliners or the July 7 bombings in London.
Security sources said the London investigation was focusing on the alleged recruitment and radicalisation of young British Muslims and the facilitation of training for terrorism purposes.
It is not yet clear whether the men were part of one group, or disparate groups who knew each other.
Sources said there was no evidence that any kind of terror attack was about to be launched and that further arrests by police were not imminent.
It is thought police will be applying to extend the time they are allowed to hold some of the men as the initial 48 hours since they were arrested will expire overnight.
The Jameah Islamiyah secondary school being searched by police opened in September 2003 as an independent day school for Muslim boys aged 11 to 16, with annual fees of £1,000.
The establishment in Mark Cross, near Crowborough, is set within 54 acres and has 100 rooms, including outhouses. Its vast grounds are often used at weekends as a retreat for Muslim families living in London wanting to escape the capital.
Bilal Patel, the school’s principal, speaking about Hamza, told the Sunday Times: “We advertise in mosques in London for camping breaks in our grounds and he and his group responded.
“When Hamza arrived we were immediately concerned about his strange behaviour. We had no idea what they were doing but we were not happy with it.”
Conservative MP Charles Hendry, whose Wealden constituency encompasses the school, has visited the establishment twice in the past five years.
He told Sky News: “People have always been aware that this school has been here – before it was a school it was already an Islamic study centre – so it’s had a long presence within the community.
“And certainly there’s been some anxiety, but from many people’s own dealings with the school they’ve found people there have been actually welcoming and been pretty open about showing people around.”
He added that residents had told him the police investigation must not be prejudged.
“(They said) let’s not jump to conclusions about what may be there. let the police do their work, let whatever follows that be done, but let’s not make conclusions at this stage before we know the outcome.”
According to its Ofsted report last December, the school had only nine boys on its roll, aged from 12 to 15.
The establishment said in a statement to inspectors that it aimed to “provide a high standard of academic and Islamic education” and to “develop real Islamic morals“.
However, Ofsted inspectors found the school failed to provide a satisfactory education for its pupils, and has significant weaknesses.
A Sussex Police spokeswoman said no arrests had been made at the school and that people living at the establishment at the time of the raid had been put up in accommodation.
A lake within the school grounds will also be investigated as part of the search.
A Metropolitan Police spokesman said: “We are searching the buildings and woodland, and the lake will be searched as well. We cannot say when that will be.”