Senior NBC officials seriously considered firing anchor Brian Williams because he lied to his viewers about riding in a military helicopter hit by a rocket-propelled grenade during the Iraq war, according to a top network official.

The ultimate decision to suspend Williams for six months was made after an internal investigation unearthed other “instances of exaggeration,” according to a person familiar with intense behind-the-scenes discussions between network officials and Williams.

During those talks, Williams failed to secure a promise that he can return to the anchor chair he has occupied for the past decade, according to two network sources, who like others interviewed for this article spoke on the condition of anonymity to discuss the sensitive personnel issue.