LONDON (AP) -- British police say seven people have been arrested on suspicion of financing terrorism overseas.
Scotland Yard says the group was arrested as part of an operation that involved U.S. Homeland Security.
The investigation involved a network suspected of illegally exporting khat, a leaf that can produce a mild high when chewed, from the U.K., where it is legal, to the U.S. and Canada, where it is a controlled substance.
British police said one woman and six men were arrested early Tuesday at four separate residences in London, Coventry and Cardiff, Wales.
They are suspected of involvement in funding a terrorist organization and laundering the proceeds of crime for that purpose, police added.
The seven are being questioned at a London police station.