Police in Germany have charged 3,500 users of a file-sharing network in the biggest single action against the illegal distribution of music online.
Police targeted people uploading "large" quantities of music illegally
The International Federation of the Phonographic Industry (IFPI) - the record industry's global body - said each could face five years in prison.
They may also have to pay compensation for offering up to 8,000 files at a time for download on the eDonkey site.
The investigation led to searches in 130 locations across Germany.
The charges affect people who upload "large amounts" of music to file-sharing networks, not those who solely download tracks to their computers or who use legitimate services such as Apple's iTunes.
"No-one should be surprised that we are stepping up our campaign in this way," said John Kennedy, chairman and chief executive of the IFPI.
"Internet piracy has hurt the whole music community in Germany, with legitimate sales falling by a third in just five years."
The organisation claimed more than 400 million music files were downloaded illegally in Germany in 2005 alone.
The German recording industry has brought legal proceedings against more than 7,000 people over the past three years.
Several hundred settlements have resulted in file-sharers paying an average of 2,500 euros (£1,705) in damages.