LONDON - Nine men accused of terrorism and conspiracy to blow up high-profile targets that reportedly included the U.S. Embassy and the London Stock Exchange in a Christmas bombing campaign made their first appearance Monday in court.

The nine range in age from 17 to 28, and most are of Bangladeshi origin. They were among 12 men arrested a week ago in three cities around Britain. Three were released without charge.

They were charged late Sunday with preparing to cause explosions during the Christmas season after a weeklong interrogation by counterterrorism police. They appeared in London's Westminster Magistrates' Court on Monday in three groups.

Antiterrorism prosecutor Sue Hemming said the nine men were charged with preparing to either commit terrorist acts or assist in them.

The men were also accused of igniting and testing incendiary materials and downloading material for the preparation of acts of terrorism, Reuters reported, and five were charged with possession of documents and records of potential use to terrorists. They are due to appear in London's central criminal court, the Old Bailey, on Jan. 14.

While few details were revealed about the targets, the BBC reported that the men were accused of carrying out reconnaissance of high-profile targets, including the American Embassy and the London Stock Exchange.

Their arrest and charges come amid continuing concerns about extremist activity in Europe. On Dec. 11 a suicide bomber killed himself in an attack in Stockholm, Sweden.

He was an Iraqi-born Swedish citizen known to have studied in Luton, England, home to three of the suicide bombers who detonated bombs on London's transport system July 7, 2005.

Dutch authorities arrested 12 Somalis in Rotterdam over the weekend. Five have since been released without charge.

Last week, Italian anarchists said they were responsible for letter bombs that injured two people at embassies in Rome. Another device was found and defused Monday at the Greek Embassy in Rome.