The nine men, including five who British news reports said were of Bangladeshi origin, were accused of offenses that included reconnoitering targets, conspiring to cause explosions and testing incendiary material. On Monday, Judge Howard Riddle ordered the men held in prison until a further hearing on Jan. 14. News reports at the time of the arrests said that the alleged conspiracy in the case was not likely to produce an imminent act of terrorism. But British broadcasters, including the BBC and Channel 4, reported late Monday that the men were accused of plotting attacks to coincide with the Christmas holidays and had reconnoitered targets like the American Embassy, the London Stock Exchange and religious and political leaders.
They were also reported to have planned to use designs from a newsletter by Al Qaeda to make parcel bombs. There was no immediate official confirmation of the reports.
On Dec. 14, the police in Germany moved against two Salafist networks suspected of seeking the imposition of an Islamic state. Those arrests were seen as a reflection of growing concern in Berlin about the radical messages of some Islamic groups.
On Saturday, prosecutors in the Netherlands said they had arrested 12 Somalis suspected of plotting a terrorist attack, but by Monday six had been released.
European concerns about terrorism seemed to mount after a suicide attack this month in Sweden, by a Swede of Iraqi descent who had been living in Britain; terrorism arrests in Spain and France; and other alarms in Germany over fears of a terrorism attack modeled on the 2008 attacks in Mumbai, India. The alerts have been given added weight by a warning in October from the State Department in Washington about reports of a planned attack in a European city.