Some may call them geeks. But when they log on they become cyber warriors, fighting for survival against alien civilizations, enemy races and war lords.

With nicknames ranging from Paranoid to DigitalMind, 700 online players from 70 countries gathered in Monza, north of Milan, on Thursday to compete in the 2006 World Cyber Games.

The battlegrounds range from tame, sporty games inspired by football and motor racing to real-time strategy games such as "Dawn of War," where players exterminate rival races in a Tolkien-like setting, or "StarCraft," in which different alien species vie for planetary domination.

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"The majority of players are viewed as somewhat nerdy. Many are young and often very shy," said Andre Zilio, 23, a Brazilian silver medallist at last year's Singapore Cyber Olympics who started playing "Pac-Man" at the age of five.

"When I was 16, I was also a complete computer geek. Now I study economics and am more interested in finance than games."

As the first contests start, dozens of youngsters appear transfixed among rows of computers, their eyes glued to the screens.

Nobody utters a word. Only the rhythmic tapping of fingertips on keyboard, mouse and joystick breaks a somewhat eerie silence.

"They are not allowed to shout, they are not allowed to stand up as they could distract other players," said Petra Weber, an Austrian-born referee who oversees "WarCraft," another strategy game. "If they do so, I give them a penalty."

But in the corner where fast-paced shooting game "Counter Strike" is being played, it's a completely different picture as players shout to team mates trying to eliminate enemies.

"Emotions run high. I used to be in the national swimming team, but here I am more nervous," said Davide Caleggi, a 22-year-old Italian who studies engineering.

MAN'S WORLD

The world gaming industry, whose estimated annual $25 billion turnover beats Hollywood box office revenues, is still a male-dominated world with few girls playing at top level.

This time, only one girl, Mitzie Valerie Eusebio from the Philippines, managed to make it to the World Cyber Games finals, her long, dark hair marking her out in a crowd of men.

"We have some female players but they are not good enough for the finals," said Weber. "Girls seem to be less interested in computers. They have other interests, like horseback riding or hanging out with their friends."

The under-30s at the World Cyber Games are not just competing for fun — winners get a slice of the $435,000 prize.

Training requires several hours of practice a day and players admit on-line games can be addictive. Early this year, a 28-year-old South Korean died of heart failure after playing "StarCraft" for 50 hours at an Internet cafe.

Yet, with such large rewards in mind, many think it is worth investing their full time in the game.

The best players, especially in South Korea, are national heroes, feted like pop stars, and many Asian players receive sponsorships that allow them to play all the time.

"I am a full-time programmer and I get a monthly salary of 3,000 yuan ($379.4) from the club that sponsors me," says Youchau Su, 23, a Chinese finalist.

"It's good if they pay you. You can spend more time playing. But the younger ones are in any case faster and when you hit 25, it's time to escape," said "StarCraft" competitor Chuanhai Zhuang.