SACRAMENTO, Calif. (AP) — A social media editor pleaded not guilty Tuesday to conspiring with the hacking group Anonymous to gain access to the Los Angeles Times' website and change the headline on a December 2010 story.

Matthew Keys, 26, made his first appearance in federal court since he was charged last month.

Keys is charged with giving the hacking group Anonymous the login credentials to the computer system of The Tribune Co., which owns the Los Angeles Times, Chicago Tribune, Baltimore Sun and other media properties.

He was fired by a Sacramento television station owned by Tribune two months before the Times' website was hacked.

The charging documents say a hacker identified as "Sharpie" used information Keys supplied in an Internet chat room to access the Times' computer system.

Keys said in a Facebook posting last month that he did not provide the login information.

"He was a journalist in that chat room, absolutely. But, I mean, he didn't do the acts he's accused of doing," his attorney, Jay Leiderman, said before Tuesday's hearing.

Prosecutors say Keys encouraged Anonymous members to hack into the Tribune's website and he applauded their success.

Keys is charged with two counts that each carry a maximum penalty of 10 years in prison — transmitting and attempting to transmit information with the intent of damaging a protected computer. He faces a third count of conspiring to transmit that information, which carries a maximum sentence of five years.

On Tuesday, however, federal prosecutors said Keys likely would serve far less than that if convicted, partly because he has no prior criminal history.

Prosecutor Matthew Segal predicted the sentence would be from 10 months to 27 months, with the possibility that he could split time between prison and house arrest.

Prosecutors did not challenge his release without bond pending a June 12 status conference.

Tribune employees spent 333 hours responding to the 2010 hacking that Keys is charged with orchestrating, costing the company of $17,650 in labor, according to an October 2012 search warrant affidavit filed by the FBI. The FBI searched Keys' three-bedroom, two-bathroom apartment looking for computer equipment.

In the affidavit, FBI agent Gabriel Andrews said there was probable cause to believe that Keys broke into the Tribune computer system after he was fired in October 2010 by the Tribune-owned FOX affiliate KTXL-TV in Sacramento. He stole an email list of FOX 40's customers, then "offered to sell this list to members of Anonymous," according to the affidavit.

"Keys also used this list to send spurious emails to FOX 40's customers and to disrupt the business operations of FOX 40," the affidavit said.

Keys' attorney, Leiderman, denied the allegations.

The television station told the FBI that Keys also changed the passwords to the station's Twitter and Facebook accounts after he was fired. He deleted 6,000 followers from the station's Twitter account and posted news headlines from the station's competitors during the four days he had unauthorized control of the accounts, according to the affidavit.

Leiderman said that involved "a dispute over ownership" of personal accounts Keys had been using on behalf of the station.

Keys was not charged with any of the alleged incidents involving FOX 40. The station referred requests for comment to Tribune Corp. spokesman Gary Weitman, who declined to comment.

Keys said via his Twitter account Monday that he has been fired by his most recent employer, the Reuters news agency.

Keys has been tireless in his use of social media, particularly Twitter. But he never said a word in court or while his attorney spoke with reporters outside the courtroom.

Leiderman would not say where his client is living aside from somewhere in Northern California. The attorney also declined to comment on Keys' firing by Reuters.

The defense attorney said his client previously turned down a plea deal that he recalled would have required his client to serve about 10 months in prison.

Leiderman said, however, that a judge could disregard those sentencing guidelines.

"You could see a judge after a trial wanting to send a message to everyone," Leiderman said. "When you look at it in that light, it could be a bit terrifying."