The LA Times said Saturday that the attack, which was first assumed to have been a server outage, hit a computer network at Tribune Publishing which is connected to the production and printing process of multiple newspapers around the country.
For Tribune subscribers, "there is no evidence that customer credit card information or personally identifiable information has been compromised", Kollias added.
The Times said that the glitch was detected Friday but technology teams were unable to fix the problem before press time.
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In other markets a similarly slimmed-down version of the Saturday newspaper will be delivered a day late, on Sunday, the three newspapers also reported.
The attack didn't compromise any subscribers, internet users or advertisers, Tribune said.
Papers that share the same production platform in LA, including the west coast editions of the Wall Street Journal and New York Times, were also hit.
And staffers at some of the affected papers said they haven't received much information from management about the extent of the cyberattack.
The Sun Sentinel published a note to its readers on its website early Saturday morning promising delivery of Saturday's paper, including coupons and advertising sections, together with Sunday's editions.
"Usually when someone tries to disrupt a significant digital resource like a newspaper, you're looking at an experienced and sophisticated hacker", said Pam Dixon, executive director of the World Privacy Forum, a nonprofit public interest research group. The systems are shared by the Times and Union-Tribune.