The employee said deputy social media editor Matthew Keys' New York office was searched and his security pass deactivated following the indictment that alleged he conspired with Anonymous to infiltrate a Tribune Co. newspaper site, The Los Angeles Times reported Thursday.
Keys posted on his Twitter page Thursday he was fine.
"I found out the same way most of you did: From Twitter," he posted. "Tonight I'm going to take a break. Tomorrow, business as usual."
Keys, 26, was charged with three hacking-related counts for the December 2010 attack on a news story on the Los Angeles Times website. The Times is owned by Tribune.
Federal prosecutors said Keys provided a user name and password for Tribune servers to hackers after he was fired from Tribune television station KTXL, Sacramento, in October 2010 and "encouraged" them to breach the site.
Prosecutors alleged a hacker accessed a news story on the Times' website and changed a headline to read: "Pressure builds in House to elect CHIPPY 1337."
The indictment said the Tribune Co. spent more than $5,000 responding to the attack and restoring its systems.
After a March 2011 Gawker article about his association with Anonymous, Keys discussed his involvement with the hacker group on his blog, the British newspaper The Guardian reported.
"I identified myself as a journalist during my interaction with the top-level Anonymous hackers and at no time did I offer said individuals any agreement of confidentiality," Keys posted. "In fact, I asked several of them for their feelings should they be exposed. They seemed, by and large, indifferent."