A Web site that earned an enterprising British student $1 million suffered a crippling attack by ransom-seeking hackers.

Alex Tew, 21, said Wednesday that his Million Dollar Homepage was targeted after he publicized how it had helped him raise money for his university studies.

Tew had sold 10,000 small squares of advertising space on the Web site for $100 each, achieving his target in four months. His initiative spawned several copycat sites.

But Tew said that on Jan. 7, he received a threat from an organization calling itself "The Dark Group," demanding that he pay them $50,000 within 72 hours or face having his site taken down.

"It was written in poor English, but the hackers asked for $50,000, saying that it was just 5 percent of what I had made," Tew said. "I did not reply to the e-mail. I had no intention of paying."

Tew ignored the threat. Hackers then initiated a so-called distributed denial of service attack, in which attackers take command of third-party computers, through a virus or other security vulnerability, and instruct them to send junk data to the target site, overwhelming servers and causing the site to crash or perform poorly.

Tew said the site now works normally.

Tew, from Wiltshire, a county in southern England, said he informed the FBI because his site is hosted in the United States.

FBI spokesman Paul Bresson said the agency was investigating.

Such extortion cases targeting Web sites are occurring with greater frequency.