Updated

The birth of Brad Pitt and Angelina Jolie's twins is turning into the type of mystery that might make a good movie one day.

The executive producer for "Entertainment Tonight" said Monday that she wanted to "see how this story plays out" before retracting a report that the twins had been born, despite a denial from Pitt's manager and a claim that someone might be posing as Jolie's personal assistant to fool reporters.

The TV show reported Friday that twin girls had been born, identifying its source as a person in the delivery room, and quoted another Web site giving the babies' alleged names.

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Rival news organizations quickly shot the story down. The Associated Press, which had picked up the "Entertainment Tonight" report after talking to executives at the show about their source, later quoted Pitt's manager saying the "ET" story was not true.

In the world of celebrity journalism, it may be the biggest story of the year.

"This is an absolutely huge, huge story for us," said Sarah Ivens, editor in chief of OK! magazine. "Essentially you have two of the most beautiful, famous people in the world. We've all seen they've had one baby, Shiloh, and it is the coolest, most adorable baby on the planet. And this time they're having two? It can't get any better."

It was "pandemonium" at the offices of Us Weekly when the "Entertainment Tonight" report was posted, said Dina Sansing, the magazine's entertainment director.

People magazine was first to report that the story was not true. Us Weekly checked its own sources and concluded the same, Sansing said.

On Monday, Jolie's attorneys advised news organizations that someone was posing as Holly Goline, Jolie's personal assistant, and had sent out false information about the movie star. The source for the "Entertainment Tonight" report was an e-mail supposedly from Goline, said an executive at the show who did not want to be identified for competitive reasons.

Was "Entertainment Tonight" punk'd? Perhaps not, the executive said.

The show initiated its own contact with Goline after hearing rumors the babies had been born in France, said the executive. The person who made the contact was an "ET" producer who had worked with Goline while at CNN and kept Goline's e-mail address, the executive said. The executive forwarded an e-mail exchange that appeared to support this version of events.

In the e-mails, Goline -- or the impostor -- said she was there for the deliveries and everyone was doing well. Pressed by "ET" for more information, the person said she could say no more.

"Entertainment Tonight" had removed its story from its Web site after the questions were raised. No mention was made of the story on Monday's show.

"Brad Pitt and Angelina Jolie are friends of `Entertainment Tonight.' We have spent years cultivating that friendship, working with them side by side on many of their projects," Linda Bell Blue, executive producer for "Entertainment Tonight" and its sister broadcast, "The Insider," said in a statement Monday. "We wish them and their children well. We are waiting to see how this story plays out."

Millions of dollars could be at stake. After Shiloh was born, Pitt and Jolie were at the forefront of a growing movement by celebrities to auction off exclusive rights to first public pictures of their babies (Pitt and Jolie donated the money to charity). Sometimes exclusive details on the birth come with these rights.

Ivens said OK! would be interested in exclusive pictures of the babies, but would not discuss whether there were any negotiations to obtain them.

Jolie has said the babies are due in August. Ivens said OK! grew more comfortable over the weekend that the "Entertainment Tonight" story was wrong because of other clues. There were no reports of flowers being delivered to hospitals, or grandparents flying in, she said, and Pitt was seen attending a sporting event over the weekend -- an unlikely spot for a new father of premature twins.