Brian Williams Inquiry Is Said to Expand -

An NBC News internal investigation into Brian Williams has examined a half-dozen instances in which he is thought to have fabricated, misrepresented or embellished his accounts, two people with inside knowledge of the investigation said.

The investigation includes at least one episode that was previously unreported, these people said, involving statements by Mr. Williams about events from Tahrir Square in Cairo during the Arab Spring.

The investigation, conducted by at least five NBC journalists, was commissioned early this year after Mr. Williams was forced to apologize for embellishing an account of a helicopter episode in Iraq in 2003. He was subsequently suspended for six months from his anchor position on the “NBC Nightly News.” The inquiry is being led by Richard Esposito, the senior executive producer for investigations, for the news division.

The review of Mr. Williams’s reporting is not finished and no final conclusions have been reached. When completed, it is expected to form the basis for a decision on whether to bring him back. It is not clear when that decision will be made.

The two people with knowledge of the investigation, who spoke on the condition of anonymity to describe internal discussions, said the episodes under review included details of the incident in Iraq in 2003; statements Mr. Williams made about a missile attack while he was traveling in another helicopter over northern Israel in 2006; and the circumstances under which he received a fragment of a helicopter that crashed during the mission to kill Osama bin Laden in 2011.

It is not clear precisely which parts of Mr. Williams’s reporting from Tahrir Square have been scrutinized by NBC or what the network’s investigation shows. But discrepancies are evident in accounts given by Mr. Williams in February 2011.

In an appearance that month with Jon Stewart on “The Daily Show,” Mr. Williams described his reporting from the square. Speaking of clashes between protesters seeking the overthrow of the Egyptian government, and a pro-government group on horses and camels, he said he had “actually made eye contact with the man on the lead horse.” Mr. Stewart then referred to reports that the pro-government group had used whips. “Yeah,” Mr. Williams replied, “he went around the corner after I saw him, they pulled out whips and started beating human beings on the way.”

The NBC News report on the clash between the protesters that day did not show Mr. Williams in Tahrir Square during the protest. Subsequent reports said that Mr. Williams was reporting “from a balcony overlooking Tahrir Square,” rather than from inside the square itself, a description that matches footage that was broadcast, and that he repeated in an interview with The New York Times last year.

NBC News and Mr. Esposito declined to comment. Mr. Williams did not reply to an email seeking comment, and his lawyer, Robert B. Barnett, declined to comment.

The people briefed on the investigation, and others who either work at NBC News or have been in contact with staff members there, say that employees in the news division provided examples for the investigating team to look into, flagging instances in which they thought Mr. Williams had exaggerated.

Mr. Williams fell from beloved news anchor to a cautionary tale in a matter of days in February, after the military newspaper Stars and Stripes raised questions about his account of an incident in the early days of the most recent Iraq war. He had been on a helicopter, he said on his own show and on “Late Show With David Letterman,” which had been shot down by rocket-propelled grenade fire.

The soldiers aboard the helicopter disagreed. In the subsequent days and weeks, additional accusations emerged that he had embellished his reports.

In the aftermath of Mr. Williams’s suspension, NBC News undertook a shake-up in its executive ranks, with Andrew Lack, a former NBC News president, coming in as head of the news division in March.

C. J. Chivers and Eric Schmitt contributed reporting.