Police say the botnet skimmed millions from bank accounts
A New Zealand teenager who admitted to taking part in an international cyber-crime network has been discharged without a conviction.
Police said the group hijacked more than one million computers and used them to take at least $20.4m (£10.3m) from private bank accounts.
Owen Thor Walker, 18, was ordered to pay $10,000 (£5,000) in damages and hand over his computer-related assets.
Police said they were interested in using his skills to fight cyber-crime.
Investigators called Mr Walker's programme one of the "most advanced" they had seen, prosecutors said.
He did not take money from people's accounts, but he was paid nearly $31,000 (£15,500) for software he designed that gave the cyber-ring access usernames, passwords and credit card details.
Judge Judith Potter dismissed the charges, relating to a 2006 attack on a computer system at a US university, saying a conviction could jeopardise a potentially bright career.
Mr Walker was detained in the North Island city of Hamilton last November as part of an investigation with US and Dutch police into global networks of hijacked PCs, known as botnets.
A botnet can be controlled over the internet by a single computer.
It installs malicious software on PCs to collect information such as login names, bank account details and credit card numbers.
Mr Walker pleaded guilty to charges of accessing a computer for dishonest purposes, interfering with computer systems, possession of software for committing crime and accessing computer systems without authorisation, the New Zealand Press Association said.
New Zealand police said he had begun committing the crimes at school, and had designed an encrypted virus that was undetectable by anti-virus software.