A malware attack is suspected of preventing production on Saturday of several newspapers, including the Wall Street Journal and Los Angeles Times.
The suspected malware attack affected the computer systems at Tribune Publishing's Southern California printing plant beginning Thursday night, said Jeff Light, the editor and publisher of the San Diego Union-Tribune. The systems are shared by the Times and Union-Tribune.
By Friday, the virus had spread to critical systems necessary to publish the newspapers, as well as the Southern California versions of the Wall Street Journal and New York Times, Light wrote in an online note to readers.
"Technology teams from both companies made significant progress against the threat, but were unable to clear all systems before press time," Light wrote. "We are working to restore full service and to continue to make our journalism available to you both in print and digitally."
Malware has in recent years becoming an increasingly common weapon against a wide variety of organizations, including hospitals, banks and government institutions.
It wasn't immediately clear whether law enforcement officials had been contacted.
Representatives for the Los Angeles Times said they had no additional information or comment, while Tribune Publishing representatives didn't immediately respond to a request for comment.
Print subscribers should get Saturday's paper delivered with Sunday's edition, Light said, citing information provided by Joe Robidoux, the Tribune Publishing's director of distribution.
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