Influential website the Huffington Post tried to ban one of its bloggers after he discovered an anonymous heckler on his blog was actually the Post's technology manager.

In his Huffington Post blog, Peter Rost exposed the identity of the heckler - known as a "troll" in blogging parlance - which prompted the Post to temporarily block his access.

He recounted the incident on a new blog site he created separately to the one co-founded by journalist Arianna Huffington.

"This is a sad day for online journalism," Dr Rost wrote on his new site. "I was terminated without any investigation of the statements in my blog post, all of which were referenced using independent sources.

"I presented facts and made no allegations. Arianna Huffington's newspaper decided to shut down the whistleblower and proved that her online magazine is no more ethical than the people and organisations she criticises on a daily basis."

Dr Rost, a former vice-president of drug company Pfizer, became suspicious after his blogs were persistently attacked by a poster called yacomink.

One comment by yacomink - "This thing reads like a sixth grader's first attempt at a research paper" - was voted a "readers' favourite comment" within half an hour of its posting, the speed of which aroused Dr Rost's suspicions.

Dr Rost had blogged at the Huffington Post for about three months and written over 60 blogs.

He was also suspicious of the incident because, out of 1,278 responses, only 18 comments had ever been popular enough to be voted a "readers' favourite".

He found yacomink's IP address and, after a further search, found a web page for Andy Yaco-Mink, which included the following: "Andy Yaco-Mink is the Huffington Post's technology manager. He lives in Brooklyn."

Dr Rost wrote a Huffington Post blog exposing Andy Yaco-Mink as the troll, suggesting that he had probably manipulated the Post's systems to get his comments placed in the readers' favourite comments.

He wrote: "In order for the Huffington Post to maintain its credibility, the site needs to avoid even the appearance of a conflict of interest or rigged rankings."

This prompted the Post to block his access to the site.

"You have not been 'fired' but rather asked to refrain from posting as our editorial staff felt that your recent blogs were not in line with the mission of our site," the Huffington Post wrote in a letter to Dr Rost.

"This was not an Arianna call. Ultimately, the decision was an editorial one - not one person to be held responsible - really," concluded the letter.

Dr Rost was later reinstated to the Huffington Post (click here to see his blog), but the incident has occurred shortly after another Huffington Post controversy - when it was forced to admit faking a blog by George Clooney.

The Oscar-winning actor forced the site to retract a blog it had passed off as his own work, when his comments had been collated from an interview.

Clooney released a statement calling Huffington's methods "purposefully misleading," and Ms Huffington acknowledged that his so-called blog was actually compiled from Clooney's recent interviews with the Guardian and CNN's Larry King.

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