New Jersey Governor Chris Christie was told about the 2013 George Washington Bridge lane closures during a 9/11 memorial ceremony the week the closures were happening—and laughed when he heard the news.

That's according to testimony in federal court from David Wildstein, the man who orchestrated the closings in his former role as interstate capital projects director for Port Authority, during a hearing on Tuesday.

The closures caused catastrophic traffic delays, and emails between the Republican governor's staffers revealed that they were part of a revenge plot to punish the mayor of Fort Lee, New Jersey, for not endorsing Christie's candidacy for governor.

During the trial that began that began earlier this month, local outlet NJ.com notes that federal prosecutors "stunned observers by contending at the trial's outset that the governor was made aware of the September 2013 closing of access lanes to the George Washington Bridge in Fort Lee in real time; that is, while cars, trucks, buses, and a few emergency vehicles sat idling for hours in a massive gridlock."

Wildstein "recalled how Mr. Christie reacted with laughter, clearly appreciating the news" after it was divulged to him, the New York Times reports. "And upon learning that the mayor's calls were being met with silence, Mr. Wildstein said, the governor said in a sarcastic tone, 'I imagine he wouldn't get his calls returned.'"

The newspaper reports that photos of Wildstein and Christie at the memorial ceremony in question do indeed show the governor laughing as the two talked:

Mr. Wildstein, who has admitted being the culprit behind the lane closings in 2013, testified as prosecutors showed a series of photographs of him, Mr. Christie and Bill Baroni, then the governor's top staff appointee at the Port Authority of New York and New Jersey, which operates the bridge, at a memorial service to mark the 12th anniversary of the terrorist attacks in Lower Manhattan.

The photos showed the three men in a loose huddle on a dirt pathway between the Sept. 11 memorial and the construction site for a tower rising at the World Trade Center site. Mr. Christie, who has previously said he did not recall the conversation, appears engaged and attentive, looking into Mr. Baroni's eyes, raising his eyes and laughing in some frames, and reaching out his hands to the other two men.

"Wildstein, in his testimony, made it clear his job at the authority was to assure that whatever Christie wanted, Christie got," reports NJ.com. "The governor, he said, was his constituency—a constituency of one.'"

Wildstein has asserted since 2014 that Christie knew about the closings, which Christie has denied.

Despite the bridge scandal, Christie campaigned for the Republican presidential nomination until quitting the race this past February and endorsing Donald Trump for the role. He currently chairs Trump's transition team, crafting the real estate mogul's agenda for a potential Trump administration.