LOS ANGELES (Reuters) – The Los Angeles Times has suspended the blog of a Pulitzer Prize-winning columnist who posed as an Internet reader to defend his column and attack his conservative foes.

The Times learned of Michael Hiltzik’s multiple identities from another blogger, Patrick Frey, who was slammed by the columnist under a pseudonym. Frey, author of the Patterico’s Pontifications blog (www.patterico.com), traced the writer back to Hiltzik’s computer.

In 1999, Hiltzik won a Pulitzer Prize at the Times with Chuck Philips for a series exposing corruption in the music industry.

Hiltzik’s spat with Frey marked the latest salvo in the battle between bloggers and the mainstream media who they accuse of arrogance and bias under the guise of objectivity.

In a statement, the Times said: “Hiltzik admitted Thursday that he posted items on the paper’s Web site, and on other Web sites, under names other than his own,”

“That is a violation of The Times ethics guidelines, which requires editors and reporters to identify themselves in dealing with the public,” the paper said. “The Times is investigating the postings.”

There was no immediate word if the newspaper planned to take any additional action against the columnist.

Hiltzik, a business page columnist who has sparred with Frey and other conservative bloggers, told Reuters he could not comment. A Times spokesman was not immediately available.

In an earlier posting on his Golden State blog, Hiltzik dismissed the complaints by Frey, a Los Angeles prosecutor, as “amusing” and overblown.

“(Frey) seems to think that pseudonymous posting is deceptive, though he can’t articulate why that should be, given the abundance of pseudonyms and anonymity on his own blog starting with the name on the banner,” Hiltzik wrote.

Frey exposed Hiltzik’s multiple identities by finding matches between the Internet addresses used by the columnist and at least two “readers” called “Mikekoshi” and “Nofanofcablecos.”

He discovered Hiltzik was also identified as “Mikekoshi” on an Internet mailing list for fans of sumo wrestling.

Dan Rather stepped down as CBS news anchor last year after a blogger-initiated furor over a story by the network suggesting President George W. Bush received favorable treatment in the National Guard during the Vietnam War.

The report was based on documents the network later acknowledged could not be authenticated. The papers had first been challenged by conservative bloggers who long claimed that Rather had a liberal bias.