Britney Spears sat back and watched as her Yorkshire terrier puppy pooped on a $6,700 designer gown at a photo shoot for OK! magazine. "I wasn't in the room but I was there to hear the upset shrieks of the stylist," editor-in-chief Sarah Ivens told The Associated Press in a phone interview Wednesday.

"Her assistant dealt with it in the end, after being asked to take care of it. They had to be asked to clear it up."

Spears also wiped grease on a designer dress, treating it like "a napkin," took frequent trips to the bathroom — leaving the door open — and complained that the high-end clothing put together for the July 19 fashion shoot weren't sexy, short or tight enough, the magazine said.

After about three hours, the 25-year-old singer bolted, walking away with more than $14,000 of borrowed apparel, Ivens said.

"I've never seen anything like it," she said. "It's definitely the most bizarre shoot I've ever been on."

Representatives for Spears had offered an exclusive interview that was intended as career comeback for the singer, Ivens said.

"What actually transpired on the day was a shock to us and left me and the whole crew feeling quite shocked and sad, really," she said.

OK! publicist Brian Strong said the magazine didn't publish the photos in its latest issue because they "weren't up to standard."

A representative at Jive Records, Spears' record label, didn't immediately return a phone call and e-mail seeking comment Wednesday.

"She needs to have a really strong team to advise her what to do, what not to do," Ivens said. "And then, if she gets that, I'm sure she can pull it around. It's all there. She's got talent. She just needs to get her priorities straight, I think."