Today's arrests follow an investigation into an apparent online scam whereby £1 million was siphoned off the accounts of customers of two banks.
The alleged scam involved emails, that appeared to be from the banks, containing "malware" which corrupted the recipients' computers.
T/DCI Jason Tunn of the Metropolitan Police's Cyber Crime Unit said he suspects they are dealing with an "international and organised crime targeting a number of bank customers in London and across the UK".
"The victims have been hoodwinked by malware-carrying emails purporting to be from their banks, and subsequently had money taken from their accounts," he said.
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England cricket coach Trevor Bayliss has described match-fixing claims around a Chennai test match against India in 2016 as 'outrageous'.
England have been beaten by nine wickets against Pakistan in the first Test at Lord's.
Mayor of London Sadiq Khan is backing the scheme.