London day trader Navinder Sarao has been formally indicted by a U.S. federal grand jury on charges of market manipulation that prosecutors say helped contribute to the 2010 "flash crash," according to a Sept. 2 court filing made public on Thursday.
The Justice Department first announced criminal charges against Sarao in April and is seeking to have him extradited to the United States to stand trial.
Sarao is accused of using an automated trading program to "spoof" markets by generating large sell orders that pushed down prices. He then canceled those trades and bought contracts at lower prices, prosecutors say.