The final numbers of the day's trading following the 20-minute
The final numbers of the day's trading following the 20-minute 'flash crash' at the NYSE on 6 May 2010 Reuters

The British high-frequency trader who was arrested over suspicions that he manipulated the futures market and played a role in sparking the May 2010 "flash crash" will fight to remain in the country as US authorities summon him.

Navinder Singh Sarao, 36, of Hounslow, London has been charged by the US Justice Department with wire fraud, commodities fraud and manipulation and "spoofing" – bidding with the intent to cancel.

Appearing at Westminster Magistrates Court, Sarao only spoke to confirm his name, address and date of birth and to state that he would be battling against the extradition ruling.

Speaking for the defence, Joel Smith said: "This is a matter that has come as something of a bolt from the blue for Mr Sarao." Asked why Sarao would fight extradition, Smith said that he was not in a position to explain why because of the "level of complexity" of the case. The defence pursued more time for a bail application.

On behalf of the Justice Authority of the United States of America, Aaron Watkins requested that bail be denied through fears that Sarao may attempt to flee.

Sarao could face a sentencing of up to 380 years in an American prison for his charges. Wire fraud, commodities fraud and manipulation, and spoofing carry punishments of 10 to 25 year prison sentences per count or a $1m (£665,300) fine in the States.

Sarao has been charged with one count of wire fraud, 10 counts of commodities fraud, 10 counts of commodities manipulation and one count of spoofing.

The Justice Department said on 21 April that Sarao used an automated trading programme to execute his scheme, which the department described as "dynamic layering".

That strategy involved placing multiple, simultaneous large volume sell orders at different price points to create the appearance of substantial supply.

He then allegedly modified the orders at a fast pace to keep them close to the market price, and cancelled them without executing them. And when prices fell, he allegedly would sell futures contracts and buy them back at the lower price.