Brad Pitt in a scene from Fight Club

Menlo Park (California), May 30 (AP): They may sport love handles and Ivy League degrees, but every two weeks some Silicon Valley techies turn into vicious street brawlers in a real-life, underground fight club.

Kicking, punching and swinging every household object imaginable ? from frying pans and tennis rackets to pillowcases stuffed with soda cans ? they beat each other mercilessly in a garage south of San Francisco.

Then, bloodied and bruised, they limp back to their desks in the morning.

“When you get beat down enough, it becomes a very un-macho thing,” said Shiyin Siou, 34, a Santa Clara software engineer and three-year veteran of the clandestine fights. “But I don’t need this to prove I’m macho ? I’m macho enough as it is.”

Inspired by the 1999 film Fight Club, starring Brad Pitt and Ed Norton, underground bare-knuckle brawling clubs have sprung up across the country as a way for desk jockeys and disgruntled youths to vent their frustrations and prove themselves. “This is as close as you can get to a real fight, even though I’ve never been in one,” the soft-spoken Siou said. Despite his reserved demeanour, he daydreams about inflicting pain on an attacker.

In recent months, police in New Jersey and Pennsylvania have broken up fight clubs involving teens and pre-teens who posted videos of their bloody battles online.

Earlier this month, in Arlington, Texas, a high school student who didn’t want to participate was beaten so badly that he suffered a brain haemorrhage and broken vertebrae.

Adult groups are more likely to fly under the radar of authorities. Menlo Park police had not heard about the local club and said they would not be likely to take action because the fights are on private property between consenting adults.

Gints Klimanis, a 37-year-old software engineer and martial arts instructor, started the invitation-only “Gentlemen’s Fight Club” in Menlo Park in 2000 after his no-holds-barred sessions with a training partner grew to more than a dozen people. Most participants are men working in the high-tech industry.