Brian Williams, anchor and managing editor of "NBC Nightly News," has been suspended without pay for six months following his continued misrepresentation of events surrounding his coverage of the Iraq War, NBC said Tuesday night.

"We have decided today to suspend Brian Williams as managing editor and anchor of NBC Nightly News for six months," NBC News president Deborah Turness said in a memo to staff sent to FoxNews.com. "The suspension will be without pay and is effective immediately. We let Brian know of our decision earlier today. Lester Holt will continue to substitute anchor the NBC Nightly News."

In the same statement, CEO of NBC Universal Steve Burke said Williams' actions were inexcusable and jeopardized the trust he has built up with viewers during his decade as the network's lead anchor. But he said Williams deserved a second chance.

"We are rooting for him," Burke said.

Williams apologized last week for saying he was in a helicopter that was hit by a grenade while covering the Iraq War in 2003. Instead, it turns out he was in a different group of helicopters and was not hit. 

Turness said the network's probe into Williams' statements is continuing.

"Brian misrepresented events which occurred while he was covering the Iraq War in 2003," she said. "It then became clear that on other occasions Brian had done the same while telling that story in other venues. This was wrong and completely inappropriate for someone in Brian's position."

Shortly after his reporting trip to Iraq in 2003, when Tom Brokaw was the anchor of "NBC Nightly News," Williams explained on-air that one of a group of helicopters he had been flying with had been hit by a rocket-propelled grenade. When he appeared on David Letterman's late-night talk show a decade later, the story changed to where his helicopter had been hit, which Williams now admits is false. It wasn't until he told the same story on "Nightly News" last month, and veterans who had been there called him out, that the embellishment emerged.

In another story about his time in Israel in 2006, Williams told his news viewers that he'd been on an Israeli helicopter and saw a trail of smoke and dust where Hezbollah rockets had landed in the Israeli countryside, and described seeing rockets being launched six miles from his location.

The story became more dramatic when he appeared on "The Daily Show" a month later.

"Here's a view of rockets I have never seen, passing underneath us, 1,500 feet beneath us," Williams said. "And we've got the gunner doors on this thing, and I'm saying to the general, some four-star, 'It wouldn't take much for them to adjust the aim and try to do a ring toss right through our open doors, would it?'"

An Israeli army official who traveled with Williams that day, Jacob Dallal, on Tuesday called the anchor's account "generally reasonable." He said it was fair to assume rockets flew beneath their helicopter.

Williams' account of seeing a body float past his hotel in New Orleans during his coverage of Hurricane Katrina has also been disputed.

In December, NBC handed Williams a new five-year contract. The Los Angeles Times reported that the deal was worth in excess of $10 million a year.

The Associated Press contributed to this report.

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