The Russian police have reportedly detained the suspected mastermind behind two well-known notorious malware toolkits.
Identified in hacking circles as 'Paunch,' the suspect was the man behind the development of Blackhole and Cool exploit kits, which are web-based applications that enable cybercriminals to attack net users with malware.
The details of the arrest however has not been confirmed by the Russian authorities, but security firms claim that there has been a drop in the use of the programmes, with no updates being pushed in over five days.
Europol spokesman was cited by the BBC as saying that the Europol and the European Cybercrime Centre have been informed that a high-level suspected cyber criminal has been arrested.
"We can only refer you to the Russian authorities, they are the ones who should speak about this topic," spokesman said.
However, Russian security firm Kaspersky chief security expert Alexander Gostev confirmed the arrest citing anonymous sources.
Another Russian service crypt.am, which allows encrypting Blackhole exploit kit, has turned offline after receiving the news of Paunch's arrest.
Launched in 2010, the Blackhole kit spread in the crimeware market during 2012 and early 2013, targeting vulnerabilities in the Java programming language, Adobe's Flash media player, Windows software and PDF files.
Once claimed to be the biggest threat of its kind, Blackhole kit had been currently put in the shade by rival kits such as Sweet Orange and Neutrino.