Police in London say they have arrested a man accused in an unauthorized trading scheme that allegedly cost Swiss bank UBS about $2 billion.

Police say Kweku Adoboli, 31, was taken into custody Thursday on the suspicion of abusing his position to commit fraud.

UBS had announced earlier Thursday that actions of the suspected rogue trader could cause overall losses during the third quarter of this year.

The investigation is ongoing. UBS maintains that no client money was involved.

UBS also has staff in the United States.