London's Metropolitan police arrested a seventh suspect after the discovery of the deadly toxin ricin in a London apartment.
The 33-year-old man was being held at a police station in Central London after having been arrested, police said. They gave no further details.
Investigators apprehended six men Sunday in north and east London and said materials at the flat in the Wood Green neighborhood had tested positive for trace amounts of ricin, a virulent poison twice as deadly as cobra venom. The first six suspects are in their teens, twenties, and thirties, and of North African origin. More arrests are possible, police said.
Police believe the suspects had intended to use the poison to kill a small number of people in hope of terrifying Britons.