Despite Nancy O'Dell's routine statement that she was leaving Access Hollywood after 13 years because of her desire "to take her career to the next level" and that her departure "is completely amicable," it was actually triggered by the on-set behavior or co-host Billy Bush, the New York Daily News reported today (Monday), citing an unnamed insider. "The atmosphere at Access Hollywood is like walking on a landmine because of Billy," the insider was quoted as saying. "He throws tantrums and tirades and oftentimes for no apparent reason. It was one of several things that had Nancy at her wit's end after 13 years." The newspaper said that O'Dell had complained repeatedly to executive producer Rob Silverstein, who refused to take action -- possibly because he and Bush are partners on Bush's syndicated nightly radio show, the Daily News suggested. Its source said that O'Dell was "subjected to Billy's outbursts and blow-ups on set just like everyone else was."