A New Zealand teenager who admitted to hacking into the University of Pennsylvania computer system was ordered Tuesday to pay more than $11,000 in fines but avoided a conviction so that he can help police solve computer crimes.

The Feb. 23, 2006, attack on the University of Pennsylvania engineering school's computer system caused part of the system to crash. Owen Thor Walker, 18, known by his online name "AKILL," also is linked to a network accused of infiltrating 1.3 million computers and skimming millions of dollars from victims' bank accounts.

Walker earlier pleaded guilty to two charges of accessing a computer for dishonest purpose, two charges of accessing computer systems without authorization, one of damaging or interfering with computer systems and one of possessing software for committing crime.

Although Walker pleaded guilty, the court discharged his case without a conviction Tuesday so that his record won't include a criminal offence — and so he can help police in the future.

Walker had faced a maximum penalty of several prison terms of up to five years. But prosecutor Ross Douch and defence lawyer Tony Balme both told the Hamilton High Court that New Zealand police were interested in using the teen's skills on the right side of the law.

Justice Judith Potter said Walker was a young man with a potentially outstanding future.

She ordered Walker to pay $7,300 US as his half share of the damage caused to the university computer and other costs totalling $3,800 US. She also ordered him to hand over his computer assets.

The case against the teenager was part of an international crackdown on hackers who assume control of computers and amass them into centrally controlled clusters known as botnets. The hackers can then use the computers to steal credit card information, manipulate stock trades and even crash industry computers, authorities said when the case first surfaced in late November.

Police said Walker did not take money from people's bank accounts himself, but that software he designed was used by other cyber criminals around the world who paid him less than $30,600 US.

Eight people have been indicted, pleaded guilty or have been convicted since the investigation began last June. Thirteen additional warrants have been served in the U.S. and overseas in the investigation.

The charges against Walker do not directly address his alleged role in the network, and police have released only a few details of the operation. They have not filed charges linked to the alleged skimming of millions of dollars, and have still not explained why no such charges have been filed.

The FBI has estimated that more than one million computers have been infected and put the combined economic losses at more than $20 million US.