A cyberattack has caused major printing and delivery disruptions for several major US newspapers, according to media reports.
The Los Angeles Times, Chicago Tribune, Baltimore Sun and other titles belonging to Tribune Publishing were affected by the attack on Saturday. Tribune Publishing said it first detected the malware on Friday.
Citing an anonymous source with knowledge of the attack, the LA Times reported the virus has come from outside the US.
"We believe the intention of the attack was to disable infrastructure, more specifically servers, as opposed to looking to steal information," according to the source.
Back-office systems used to publish and produce "newspapers across our properties" were hurt by the malware, Tribune Publishing spokeswoman Marisa Kollias said.
"Every market across the company was impacted," Kollias added, but refused to give more specifications on the disruptions.
"There is no evidence that customer credit card information or personally identifiable information has been compromised."
However, there were reports showing that when some LA Times readers sought to inquire about their print edition, the customer service phone lines were on the blink.
In addition, employees at two papers using Tribune software told CNN Business that the time card system used to keep track of working hours was offline for a while.
The malware also affected West Coast editions of the Wall Street Journal and The New York Times, which share the same production platform in Los Angeles.
Investigators at the Federal Bureau of Investigations did not give any immediate comments. However, a Department of Homeland Security official said in a statement, "We are aware of reports of a potential cyber incident affecting several news outlets and are working with our government and industry partners to better understand the situation.”