Spanish police have captured a cyber crime gang made up of Ukrainians and Russians which allegedly stole more than €1 billion from financial institutions worldwide in a five-year spree.
The gang's alleged mastermind, identified as a Ukrainian and named only as Denis K, was arrested in the coastal city of Alicante, 220 miles south-east of Madrid, according to Spanish police and Europol.
Three suspected accomplices, said to be Russian and Ukrainian, were also arrested.
The gang used malware to target more than 100 financial institutions worldwide, sometimes stealing up to €10 million in each heist. Almost all of Russia's banks were targeted, and about 50 of them lost money in the attacks, authorities said.
The gang sent phishing emails with a malicious attachment to bank workers, Europol said. The software gave the gang remote control of infected machines, providing them with access to the internal banking network and infecting servers controlling ATMs.
ATMs were instructed to dispense cash at a pre-determined time, and the money was collected by organised crime groups supporting the main gang.
The gang converted its illicit gains into bitcoins and used the cryptocurrency to purchase assets in Spain, including houses and vehicles.