Police have opened a criminal investigation into a Russian couple accused of breaching the law on intellectual property rights to the tune of $1.25 billion, Interfax reported Monday.

The unidentified couple registered a file-sharing web site, Interfilm, hosted it on a Dutch server, and uploaded several dozen pirated movies onto it, the report said, citing the Interior Ministry's Investigative Committee.

In 2007 and 2008, Interfilm was one of the most popular torrent-tracker web sites, with so many pirated movies downloaded through it that their combined license agreements would cost 38.7 billion rubles, investigators said.

Investigators have tracked down about two dozen of the most active users of the web site and are considering opening criminal cases against those who kept large numbers of pirated movies on their personal computers.

Boosting efforts to fight piracy is a major U.S. demand as Russia negotiates its entry into the World Trade Organization.

In Russia, the violation of intellectual property rights is punishable by up to five years in prison.