Within the anti-terrorist raid, London police arrested 9 people.
They were arrested by the members of the Metropolitan Police Service"s Counter Terrorism Command on Thursday.
All of them probably are the members of the prohibited group. The arrested men, aged between 22 and 47, are in custody at stations in central London.
It is known that one of them is a radical Islamic preacher Anjem Choudary.
Earlier, Prime Minister Cameron said he would ask the Parliament to allow the country"s participation in military operations against the Islamic state.