Updated Sunday at 12:53 p.m. ET
Jeff Light, editor and publisher of the San Diego Union-Tribune, began Saturday morning by issuing an apology. "Most Union-Tribune subscribers were without a newspaper this morning as a computer virus infected the company's business systems and hobbled the ability to publish," Light wrote.
In a note posted on the Union-Tribune's website, Light described a computer virus that affected the computer systems for Tribune Publishing, the media company that used to own the Union-Tribune and currently owns multiple newspapers including the Chicago Tribune, The Baltimore Sun and the Orlando Sentinel. Even though the Union-Tribune is no longer owned by Tribune Publishing, Light said it is "still transitioning away from the Tribune systems."
Marisa Kollias, spokesperson for Tribune Publishing, wrote in a statement to NPR's David Folkenflik: "On Friday, some of the print production systems at Tribune Publishing were interfered with, causing a delay in our production schedule." Kollias said no personal data of subscribers, online users or advertising clients was compromised as a result of the interference, and news and all regular features are available online.
Phone lines for the Los Angeles Times were jammed Saturday morning, as many subscribers to that paper also woke up without their physical copy. The paper's main Twitter account has been responding to individual complaints with phrases like, "We've had a ton of delivery problems today which is why our lines are busy" and "You're right! We have had big issues with delivery today and we apologize." The Los Angeles Times, like the Union-Tribune, used to be owned by Tribune Publishing and still uses some of its systems.
Hillary Manning, spokesperson for The Los Angeles Times, wrote in an email to NPR:
"A computer virus infected the business systems associated with the printing process. This has caused delayed and incomplete printing of the Los Angeles Times, San Diego Union-Tribune and other publications which are printed at our facility. As a result, many home-delivery customers experienced delayed deliveries this morning, and some customers may not have received their paper."
Manning said subscribers whose papers weren't delivered would receive Saturday's issue with the Sunday paper.
Joseph Robidoux, director of distribution for The Los Angeles Times and The San Diego Union-Tribune, said as of Sunday morning they were still working around lots of technical issues.
Sunday papers arrived to distribution centers around 60 minutes later than normal but that's "obviously much better than yesterday," Robidoux added.
Light says production of The Wall Street Journal and The New York Times was also affected as a result of Saturday's delays at the Olympic Printing Plant in L.A.
Eileen Murphy, a New York Times spokesperson, tells NPR in an email that Times print circulation in some parts of the L.A. market was impacted. She says about 20,000 Saturday issues will arrive on Sunday instead.
According to reporting from The Los Angeles Times, the company believes the production of other newspapers may also be affected but has yet to confirm details.