Police have arrested four suspected cyber criminals and seized £80,000 in cash and a live grenade after the theft of £1m from two banks.
Two 31-year-old men, a 27-year-old woman and a 24-year-old woman were arrested on suspicion of conspiracy to defraud, conspiracy to launder money and possession of an explosive.
The men are being held in custody while the women have been bailed until early next year.
The arrests and seizures followed raids on properties in Enfield and Islington, in north London by the Metropolitan Police’s cyber crime unit (MPCCU).
Detectives from the unit are investigating the thefts linked to malicious software inadvertently downloaded by customers of the banks.
The malware downloads were triggered by opening emails that appeared to be from the targeted banks.
The malware enabled criminals to transfer a total of £1m to a series of other accounts, to be laundered and withdrawn as cash, police said.
More on cyber threats to banks
- Banks to test cyber defences
- Bank of England and Treasury set banks cyber security deadline
- Banks' perception of cyber risks increases after several attacks
- Banks and governments targeted by invisible hijacking attacks
- More than half top bank websites hacked, study shows
- Financial services watchdog announces mobile banking report
- Cyber attacks top banking risk, says Bank of England
"These arrests by the Met's cybercrime unit follow an investigation into what we suspect is international and organised crime targeting a number of bank customers in London and across the UK,” said detective chief inspector Jason Tunn of the MPCCU.
“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.
Police recovered several computers, smartphones and other media devices, as well as luxury goods in the co-ordinated raids.
The MPCCU has asked several banks to freeze a number of accounts linked to the investigation.
The National Audit Office estimates that cybercrime costs Britain an estimated £18bn to £27bn every year.
Cyber security firm Check Point said bank customers must watch out for emails that appear to have been sent by their bank and contain links to websites or attachments.
“In late 2012, the Eurograbber attack siphoned £30m from bank accounts in Europe using sophisticated malware that infected users’ PCs from emails,” said Keith Bird, Check Point’s UK managing director.
“These attacks are complex and stealthy, and exploit customers’ trust,” he said.
Bird warned users of online banking facilities should be wary of any emails containing links or attachments, and advised them to keep anti-virus software up to date and install a personal firewall.
There is growing international concern about the safety of financial markets in the face of increasingly sophisticated cyber attacks.
In September, Scott Borg, chief of the US Cyber Consequences Unit, said he believed manipulation of international financial markets will be the next evolution of cyber crime.
In November, UK banks and financial institutions took part in Operation Waking Shark 2, which was designed to simulate a major cyber attack on the payments and markets systems.
The test was monitored by the Bank of England, Treasury and Financial Conduct Authority who are due to publish a report on the ability of the UK’s core financial services providers to withstand cyber attacks.