Culprit behind Oscars Best Picture flub did something he was asked not to do moments before error

In the days following the now-infamous Best Picture mishap at Sunday night's Oscars, more information has emerged about how the mistake could've possibly occurred.

PricewaterhouseCoopers, the account firm that has been in charge of the Oscars results for decades, released another statement on the matter on Monday, calling out partner Brian Cullinan as the culprit behind the flub.

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"PwC Partner Brian Cullinan mistakenly handed the back-up envelope for Actress in a Leading Role instead of the envelope for Best Picture to presenters Warren Beatty and Faye Dunaway," the statement read. "Once the error occurred, protocols for correcting it were not followed through quickly enough by Mr. Cullinan or his partner."

See photos from the moment:

One thing the firm's statement didn't address? The fact that Cullinan tweeted a since-deleted photo of Best Actress winner Emma Stone moments before the incident occurred. Not only that, but it also came to light that Cullinan was specifically asked not to post to social media during the ceremony.

"Brian was asked not to tweet or use social media during the show," a source told People. "He was fine to tweet before he arrived at the red carpet, but once he was under the auspices of the Oscar night job, that was to be his only focus. Tweeting right before the Best Picture category was announced was not something that should have happened."

Cullinan was one of two PwC employees in charge of bringing the result envelopes to the ceremony and then handing them to the presenters before they took the stage. Cullinan had walked the red carpet with his colleague Martha Ruiz carrying identical briefcases full of the results before they took their places at either end of the Oscars stage. Cullinan, though, was the one to give the wrong envelope to Warren Beatty and Faye Dunaway.

Cullinan has yet to speak on the incident.

See all of the red carpet arrivals at the 2017 Oscars:

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