Top Roger Ailes Adviser Fired and Escorted From Fox News Building (Exclusive)

Brian Lewis and Roger Ailes

UPDATED: Brian Lewis, executive vp corporate communications, was ousted after an investigation found breach of contract and "issues relating to financial irregularities," the network says in a statement.

Brian Lewis, a Fox News Channel veteran executive considered the right-hand man to Roger Ailes, was working on his separation agreement Tuesday after having been fired and escorted from his office last month over what insiders are calling financial issues and other performance problems, The Hollywood Reporter has learned.

"After an extensive internal investigation of Brian Lewis' conduct by Fox News, it was determined that he should be terminated for cause, specifically for issues relating to financial irregularities, as well as for multiple, material and significant breaches of his employment contract," a company spokesperson said Tuesday. "He was terminated for cause on July 25."

Lewis, who had been a top executive since Ailes founded the powerful cable news network 17 years ago, was most recently executive vp corporate communications, overseeing public relations not only for Fox News but also the Fox Business Network, Fox Television Stations and 20th Television.

Attempts to reach Lewis were not successful. An e-mail to Lewis at Fox News prompted an "on vacation" auto-reply message.

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Lewis also was senior adviser to Ailes, who was handpicked by Rupert Murdoch to create Fox News as its founding CEO. Today, Ailes also is chairman of Fox Television Stations. Before his firing, Lewis often was a spokesman for Ailes, who asked him to act as liaison between him and Zev Chafets while Chafets was writing his recently released book, Roger Ailes: Off Camera, a mostly flattering biography of Ailes.

Insiders say that their close relationship made it difficult for Ailes to cut Lewis loose, but the financial issues his actions raised -- details of which were not available Tuesday -- coupled with complaints about complacency and other matters, left Ailes feeling as if he had no other choice.

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Though the exact nature of the problems swirling around Lewis weren't known to rank-and-file staffers, witnesses say they amounted to a serious enough breach that it was necessary he be escorted from his office at Fox News headquarters in New York.

Lewis joined Fox News in April 1996 -- six months prior to the channel's debut -- as vp media relations. He was made senior vp in 2000 and executive vp in 2006.

As of Monday, the Fox News website still identified Lewis as a top executive and a biography listed among his accomplishments: "Launching the Fox News Channel to overwhelming consumer awareness, creating and implementing successful campaigns favorably positioning FNC against competing networks and corporations, and handling all crisis situations that have threatened the network."

On Tuesday, the information on the website about Lewis was taken down.