Spanish authorities have detained a man they believe to be one of the heads of the notorious Reveton malware gang.
Police said that the man, who is a Russian national, is currently being held in Dubai and is awaiting extradition to Spain, where the Reveton gang is believed to have based part of its operation.
According to researchers from Trend Micro who worked with the Spanish to track down the group, the Reveton crew has been overseeing a series of malware attacks which extort ransom money from victims.
Researchers and law enforcement believe that the payments were being funnelled from the victim PCs through accounts in Spain. Profits from the operation were then sent back to individuals in Russia.
The malware loads on the victim PC and then demands that the user make a payment in order to regain access to their system. In some instances, Reveton campaigns have even posed as alerts from law enforcement agencies.
The Reveton group is believed to have netted more than €1m over the course of the malware campaign.
While joint legal campaigns from security firms and law enforcement groups have led to a number of high-profile arrests in recent years, malware operations and botnet chains have proven extremely difficult to kill over the long term.
Trend Micro security director Rik Ferguson told V3 that while the operation is important, more work still needs to be done to fight cybercrime in Europe.
"There are multiple groups running ransomware type scams, but Europol estimates that the Reveton gang in particular had hundreds of thousands of victims of mostly European countries," Ferguson told V3.
"Given the fact their money laundering outfit was laundering over €1m euros a year, this is a very significant arrest. However, this doesn't constitute the entirety of the Reveton gang and the malware is still out there and still being used by other threat actors."
Earlier this week, researchers noted that the Kelihos botnet has apparently recovered from a takedown campaign and could soon be larger and more dangerous than it had been before the original shutdown.