Spanish police say they have arrested a former JP Morgan Chase trader wanted by the United States for allegedly falsifying bank records to cover up $6bn in trading losses.
A statement said that Javier Martin-Artajo, 49, was arrested Tuesday after he presented himself at a police station in Madrid, the Associated Press reports.
US prosecutors earlier this month filed criminal charges against Martin-Artajo, a Spanish citizen, and another ex-JP Morgan trader, Julien Grout.
Martin-Artajo and Grout were accused of marking up the market value of an investment portfolio to hide its plummeting value.
The portfolio eventually incurred a $6bn loss, which was attributed for months to Bruno Iksil, a trader who became known as the "London Whale".
Martin-Artajo was to be brought before the National Court in Madrid as part of extradition proceedings.
Reasons to be cheerful
Total investment reaches £9m
Medium to long-term capital growth