IOWA CITY, Iowa -- As Agriprocessors Inc. was getting stung by criticism after a federal immigration raid snared hundreds of its workers, "a blog by people who live and work in Postville" appeared in its defense in May.

The blog defended the hiring practices of the plant in the small Iowa community, rebutted allegations in a federal affidavit and railed against the media, government and a labor union.

"We've had enough of every organization with an agenda cynically misrepresenting our town and workplace to further their own ends," PostvilleVoices.com said. It added that "there is one thing we do know -- the people that run Agriprocessors are good, decent, honest people and we trust that they have acceptable answers."

It was grassroots activism at its finest -- if you think the son of the plant CEO at the time and two of his friends count as grassroots activists.

The anonymous blog was an odd twist in the case against Agriprocessors -- since expanded to include child-labor charges -- as well as an example of an increasingly common practice known as astroturfing -- inventing grassroots support without the trouble of engaging a community.

"There's not a big penalty associated with doing this and being caught," said Herman B. Leonard, a professor at Harvard University's John F. Kennedy School of Government. "There's a potentially substantial benefit, ... so if you get away with it, it's a plus. If you don't, they say, 'Well, it's not too surprising.' "

Aiding the deception was a new development in astroturfing: Web hosts that protect a site owner's identity from anyone not holding a subpoena.

Dan Handy, the general manager of the Postville site's Web host, Bluehost.com, said the intention of his site is to stop spammers from stealing personal information from online registries. But he acknowledged there's also the benefit of complete anonymity.

Tracking such sites is difficult because of the anonymity, but other examples include:

• Tennesseans Against Teen Drinking was promoted as a font of grassroots opposition to Internet sales of alcohol, but its Web site didn't mention that the group was backed by major alcohol lobbying firms that wanted to kill legislation allowing people to buy wine from other states.

• Consumers Organized for Reliable Electricity ran a Web site warning about the consequences of an electricity rate freeze. It was later revealed the group was largely funded by Illinois electric utility company Commonwealth Edison.

The pro-Agriprocessors site was formed by 24-year-old Getzel Rubashkin and two friends not connected to the company. His father, Sholom Rubashkin, was until this summer the plant's CEO, and his grandfather, Aaron Rubashkin, owns the New York-based company.

The blog drew the suspicion of area residents, including a radio host. Getzel Rubashkin said in an interview with the host that he provided some technical assistance for the site, then acknowledged in an interview last month with The Associated Press that he and his friends created it.

Rubashkin, who lives in Postville and worked part time at Agriprocessors, said he didn't use plant money to work on the blog, but did film the interviews in the plant and had unfettered access to it and its employees.

Getzel Rubashkin said he and his friends started the Web site about two weeks after the May 12 raid, in which 389 workers were arrested on immigration charges. The hope, he said, was to counteract false media reports.

Rubashkin said that, in hindsight, he should have attached his name to the site, but that he wanted the claims to stand on their own merits.

"I do see now in retrospect that it could look deceptive," Rubashkin said. "That was not the intent."

He said he had been discouraged by management from maintaining the Web site and expressing views there.

"Humanity benefits from honest communication," Rubashkin said.

A call to Agriprocessors seeking comment was not returned Friday.

Aside from picking a Web host that provided anonymity, he said, he and his friends didn't try to fool anyone.

"No extra effort went into pretending that this was a neutral site or that the blogger didn't have any opinion," Rubashkin said.

At the same time the Web site was supposedly giving voice to Postville residents, the company became tangled up in an embarrassing situation in which a New York public relations firm paid by Agriprocessors had to apologize when an employee falsely used a rabbi's name to post Web comments about the plant and question its critics.

The rabbi, Morris Allen of Minnesota, threatened legal action but said Monday that the matter was resolved "in an agreed-upon manner." He declined to be specific.

Forms of astroturfing can pay off for companies and interest groups, and the practice is undoubtedly becoming more common, said Eric Dezenhall, who heads Dezenhall Resources, a Washington, D.C., corporate crisis-management firm.

Dezenhall recalls talking to a group representing a prospective client who spent time building blogs. He asked the lead manager whether the group "had a roomful of people who pretend that they're Mr. Joe Citizen on blogs all day."

"There was a lot of squirming," said Dezenhall, who has written two books on astroturfing.

He said he opted not to work with them out of concern that the practice would backfire. And that's something companies and groups should keep in mind before setting loose a roomful of bloggers-for-hire or launching a positive-spinning Web site, he said.

"If you're under fire for something, a wholesale front group causes the media, regulators, legislators, natural opponents to dig in, because it validates the notion that (the group is) doing something wrong," he said.

In the weeks since the site announced its final chapter, a new Web site has emerged, one that Getzel Rubashkin said he has nothing to do with.

Agrifacts.info clearly states that it is run by "friends, family and supporters of Agriprocessors and the Rubashkin family."

Agriprocessors also operates a plant near Gordon, Neb.