A Russian programmer who masterminded the SpyEye bank hacking tool has pleaded guilty to a related charge in the US.
Aleksandr Panin is alleged to have developed the Trojan malware that has become one of the most commonly used bank account hacking kits around the world.
The kit uses a range of techniques to siphon off the money of victims and prosecutors estimate that more than 1.4 million PCs have been infected since it was first released in 2009.
Panin has pleaded guilty to a single count of conspiracy to commit bank fraud and wire fraud.
Federal prosecutor John Horn said Panin was "one of the pre-eminent cybercriminals that we've been able to apprehend and prosecute so far".
The FBI estimates that 10,000 bank accounts were compromised by the SpyEye Trojan last year alone, with one individual, who purchased the toolkit online, claiming to have made $3.2 million using the software in just six months.
Panin is due to be sentenced on 29 April.
By Gary Cooper