Navinder Singh Sarao: "Flash Crash" trader fails to post £5m bail and claims he 'did nothing wrong'

The London trader accused of helping to bring financial markets to a brief standstill during the 2010 "Flash Crash" will remain in custody after failing to overturn his bail conditions, despite claiming he was just 'being good at his job'.

Navinder Singh Sarao, the so-called Hound of Hounslow, was arrested last month after US authorities alleged his trading activities contributed to a sharp stock market plunge that wiped billions of dollars from the value of American shares in a matter of minutes.

He has been charged with wire fraud, commodities fraud and market manipulation and US prosecutors want him to be extradited.

Appearing at Westminster Magistrates court, Sarao refuted the allegations saying: "I haven't done anything wrong apart from being good at my job."

"How is this allowed to go on, man?"

Last week he was given an extra seven days to come up with £5 million bail money set by a judge.

Appearing today at Westminster Magistrates court, the trader, who lives and works from his parents' modest Hounslow home, again did not satisfy his bail conditions.

Sarao's lawyers instead asked that he be freed until an extradition hearing in exchange for a £50,000 security put up by his parents, according to reports.

Sarao, who the FBI has accused of stashing up to £26 million in offshore bank accounts in the Caribbean, has reportedly been unable to get hold of the £5 million due to an asset freeze imposed by the US.

District Judge Elizabeth Roscoe declined to modify the bail.

The 36-year-old was returned to Wandsworth prison following the hearing.

Additional reporting by Press Association