Gamers competing against rivals around the globe in online multiplayer games have a new force protecting them -- teams of virtual detectives.

While some companies cause havoc with PC users via e-mail spam and viruses, a new type of spam company is targeting the huge worlds of massively multiplayer online (MMO) videogames like Activision Blizzard's World of Warcraft.

In-game characters controlled by individuals working for spam companies infiltrate these virtual worlds and bombard players with unsolicited ads for the sale of in-game virtual items like swords and even playable characters.

This type of activity is forbidden by all game publishers within their player rules of conduct so Sony Online Entertainment (SOE), which oversees MMO games like EverQuest, Star Wars Galaxies and Free Realms, is flexing its online muscle.

SOE has created the Norathian Underground Gnome Investigation Team or NUGIT, which refers to the fantasy world of Norath in Everquest.

This nine-member team focuses on in-game fraud, working like detectives as they police SOE's game worlds in search of spammers and try to uncover their entire operations.

People get very frustrated when they see spam. It's the equivalent of junk mail and you're getting this in-game and it's very frustrating, said John Smedley, president of Sony Online Entertainment.

To date, SOE has closed 295,000 subscription accounts across its MMO games as a result of NUGIT's patrols.

Brad Wilcox, director of customer support at SOE and manager of NUGIT, said these farming organizations are very organized.

WHERE THERE'S A DEMAND...

Companies hire players to log online and build up in-game characters and accrue virtual items and gold by performing mundane activities.

These items are transported via mules to runners, who sell these items to players for cash through third-party sites.

Players looking to upgrade to better characters or access more powerful weapons can buy these items directly, saving themselves hours of playing the game to get these upgrades.

Game publishers don't like third-party companies making money off their in-game world -- and many legitimate players don't like dealing with these interruptions to gameplay.

Once a player reports a spammer or farmer to NUGIT, we watch the individual account and track other accounts of the mules and runners associated with the organization, explained Wilcox.

Rather than closing down one account, we'll follow the individual and end up banning as many as 100 to 200 accounts based off one tip.

Smedley estimates the worldwide take of farmed virtual items is $2 billion a year industry via these third-party companies.

A lot of them are offshore. It's very difficult to stop somebody that's in another country, particularly one where the laws aren't friendly to the United States and it can be very challenging, he said.

SOE does offer an alternative to its players, letting them convert real cash into virtual cash to purchase in-game items from the publisher legally and safely.

Since MMO game publishers rely on monthly subscription fees from players, ensuring they keep enjoying the game is key but this does open up cash opportunities for farmers.

As long as players want in-game items so much that they're willing to spend real-world money on them, this is going to be a problem, said Chris Baker, videogame editor at Wired Magazine.

(Editing by Belinda Goldsmith)