An "outraged and deeply saddened" Christie responded by saying he was misled by his aide, and he denied involvement in the apparent act of political payback.
The messages were obtained by Action News, The Associated Press, and other news organizations Wednesday amid a statehouse investigation into the whether the lane closings that led to the tie-ups were retribution against the mayor of Fort Lee for not endorsing Christie for re-election last fall.
"Time for some traffic problems in Fort Lee," Christie deputy chief of staff Bridget Anne Kelly wrote in August in a message to David Wildstein, a top Christie appointee on the Port Authority of New York and New Jersey.
"Got it," Wildstein replied. A few weeks later, Wildstein closed two of three lanes connecting Fort Lee to the heavily traveled George Washington Bridge, which runs between New Jersey and New York City.
The messages do not directly implicate Christie in the shutdown. But they contradict his assertions that the closings were not punitive and that his staff was not involved.
Democrats seized on the material as more evidence that the potential Republican candidate for president in 2016 is a bully.
The messages "indicate what we've come to expect from Gov. Christie - when people oppose him, he exacts retribution. When people question him, he belittles and snidely jokes. And when anyone dares to look into his administration, he bullies and attacks," Democratic National Committee chairwoman Debbie Wasserman-Schultz said.
In a statement issued late Wednesday, Christie said: "I am outraged and deeply saddened to learn that not only was I misled by a member of my staff, but this completely inappropriate and unsanctioned conduct was made without my knowledge."
"People will be held responsible for their actions," he added, but gave no details.
Kelly had no immediate comment.
Fort Lee Mayor Mark Sokolich called it "appalling" that the traffic jams appear to have been deliberately created.
"When it's man-made and when it was done with venom and when it was done intentionally, it is, in my mind, the prime example of political pettiness," he said. He said the gridlock put people in danger by holding up emergency vehicles, and he added that those responsible should resign.
While Sokolich is a Democrat, Christie sought bipartisan support during his re-election campaign to bolster his image as a pragmatic leader willing to work with his political opponents.
Democratic state Assemblyman John Wisniewski, who has been leading the investigation, said the material in the documents is "shocking" and "outrageous" and calls into question the honesty of the governor and his staff.
The tie-ups occurred between Sept. 9 and Sept. 13. Port Authority officials later said the closings were part of a traffic study. But no study has been produced.
As the controversy heated up over the past few weeks, Wildstein resigned, as did Port Authority deputy executive director Bill Baroni, another Christie appointee. Wildstein, a childhood friend of the governor, is scheduled to testify on Thursday before a state Assembly committee but is fighting the subpoena.
One of the released texts came from Sokolich, who pleaded on the morning of Sept. 10: "The bigger problem is getting kids to school. Help please. It's maddening."
Within minutes of Sokolich's plea, an unidentified person commented in a text message: "Is it wrong that I am smiling?" Someone joked in another text that the youngsters referred to by Sokolich "are the children of Buono voters" - a reference to Christie's Democratic opponent for governor, state Sen. Barbara Buono.
Also among the correspondence, some of which was blacked out, is an email from Wildstein to Kelly on Sept. 7, two days before the lane closings. He said he would call her "to let you know how Fort Lee goes."
Most of the emails were sent using private accounts rather than government ones, which would be subject to open records laws and therefore public.
The Democratic National Committee seized on the disclosures, releasing a web video that details Christie's prior assurances that neither he nor his staff had anything to do with the lane closings.
"I've made it to very clear to everybody on my senior staff that if anyone had any knowledge about this that they needed to come forward to me and tell me about it, and they've all assured me that they don't," Christie said in mid-December.
Wasserman-Schultz said the new material proves that "the governor's office ordered lane closures that were intended to make first responders experience delays, kids sit gridlocked on the first day of school, and commuters hit logjams, to punish the Democratic mayor who didn't endorse Chris Christie's re-election bid."
Sokolich said that because of the traffic backup, emergency calls that average a two- or four-minute response time took up to 16 minutes.
"To me it's appalling and I got to tell you, somebody owes a lot of people a lot of apologies," he said. "Somebody ought to contact families waiting two, three, four times the response times when their loved ones had chest pains. Someone has to apologize to the thousands of families who couldn't get their kids to the first day of school on time."
Fort Lee Councilwoman Ila Kasofsky said she knows of one woman who couldn't get over the bridge to be with her husband, who was undergoing a stem cell transplant, and another who couldn't get to New York to be with her son as he went through kidney dialysis.
Also, she said, the heavy traffic delayed the search for a missing child, who was later found.
"I think this is 10 times worse than Watergate. Because this affected so many more lives and their health and safety," she said.
Full statement from Governor Chris Christie:
"What I've seen today for the first time is unacceptable. I am outraged and deeply saddened to learn that not only was I misled by a member of my staff, but this completely inappropriate and unsanctioned conduct was made without my knowledge. One thing is clear: this type of behavior is unacceptable and I will not tolerate it because the people of New Jersey deserve better. This behavior is not representative of me or my Administration in any way, and people will be held responsible for their actions."
Associated Press writers Katie Zezima in Newark, N.J., and Steve Peoples in Washington contributed.