The 18-year-old man arrested by German police on suspicion of creating the destructive "Sasser" computer worm confessed to police that he had programmed the worm, a police spokesman said today.
"He made a confession to police," said spokesman Mr Frank Federau for Lower Saxony police.
Mr Federau did not give any details on where the admission was made or whether the man went to police before they searched his parents' home, where he also lives, on yesterday afternoon.
Mr Federau said more details would be available at a police news conference later.
Sasser, a tenacious computer worm, is expected to infect millions of machines before it runs its course.
Since appearing a week ago, it has wreaked havoc on personal computers running on the ubiquitous Microsoft Windows 2000, NT and XP operating systems, but is expected to slow down as computer users download anti-virus patches.