Londoners react to the newsroom shooting in Paris.
By the hundreds, they gathered outside the National Gallery at Trafalgar Square.
A silent vigil -- for ten journalists and two police officers killed earlier when suspected Islamist militants attacked the satirical French weekly, Charlie Hebdo.
'I am Charlie', their signs read.
Their pens held up -- like swords.
(SOUNDBITE) (English) VIGIL ATTENDEE, SAYING:
"I think what shocks me the most is that it has actually happened in this day and age. That some men can just walk into a building and decimate a whole team."
Eleven people were also wounded in the attack, several critically.
Terrorism experts say the gunmen behaved like trained commandos, and that the assault was apparently well-planned.
Witnesses say the journalists had gathered for a weekly meeting and that the gunmen called out some of their victims by name.
Security in France is at its highest level and other governmen
