LOS ANGELES (CBSLA.com/AP) — The FBI is now involved in a massive celebrity photo hack scheme.

Nude images of celebrities were stolen from private accounts and leaked online.

Jennifer Lawrence, 24, is one of dozens of female stars who were targeted, although the authenticity of many of those images couldn’t be confirmed. The Oscar winner has contacted authorities to investigate who’s responsible for the leak and threatened legal action, her publicist said.

The source of the leak is unclear.

KNX 1070’s Margaret Carrero reports intimate images of Lawrence, who stars in “The Hunger Games” film franchise and won an Academy Award for her role in “Silver Linings Playbook,” began appearing online Sunday.

“This is a flagrant violation of privacy,” Lawrence’s publicist Liz Mahoney wrote in a statement. “The authorities have been contacted and will prosecute anyone who posts the stolen photos of Jennifer Lawrence.”

Mahoney declined to provide further details, including which authorities were contacted. Lawrence is a three-time Oscar nominee.

Apple spokeswoman Natalie Kerris said the company was investigating whether any iCloud accounts had been tampered with, but she did not give any further details.

“We take user privacy very seriously and are actively investigating this report,” she said.

Actress Mary Elizabeth Winstead also confirmed that nude photos of her were posted online.

“To those of you looking at photos I took with my husband years ago in the privacy of our home, hope you feel great about yourselves,” Winstead posted on Twitter. Winstead, who starred in “Final Destination 3” and “Abraham Lincoln: Vampire Hunter,” wrote that she thought the images had been destroyed.

“Knowing those photos were deleted long ago, I can only imagine the creepy effort that went into this,” Winstead wrote.

The FBI has investigated previous leaks of nude celebrity images, including leaks involving Scarlett Johansson, Mila Kunis, Christina Aguilera and footage of television sports reporter Erin Andrews in a Tennessee hotel room. Those cases resulted in convictions.

In a statement, FBI spokeswoman Laura Eimiller said, “The FBI is aware of the allegations concerning computer intrusions and the unlawful release of material involving high profile individuals, and is addressing the matter. Any further comment would be inappropriate at this time.”

Eimiller declined to comment on whether the agency was involved.

How widespread the hacking of celebrities photos was is not immediately clear. Some of the images were quickly denounced as fakes.

Some cybersecurity experts speculated that hackers may have obtained a cache of private celebrity images by exploiting weaknesses in an online image-storing platform.

“It is important for celebrities and the general public to remember that images and data no longer just reside on the device that captured it,” security researcher Ken Westin wrote in a blog post Monday. “Once images and other data are uploaded to the cloud, it becomes much more difficult to control who has access to it, even if we think it is private.”

Here in the Southland, some fans were less than sympathetic to calls for privacy for celebrities who take naked images of themselves.

“They’re the ones who took the picture,” one man said.

“I mean, anything you put on the Internet, you kinda run the risk,” another fan said. “They should know better.”

Private information and images of celebrities are frequent targets for hackers. Last year, a site posted credit reports, Social Security numbers and other financial info on celebrities, including Jay Z and his wife Beyonce, Mel Gibson, Ashton Kutcher and many others.

Johansson, Kunis and Aguilera were hacked by a Florida man, Christopher Chaney, who used publicly available information to hack into the email accounts of more than 50 people in the entertainment industry.

“I have been truly humiliated and embarrassed,” Johansson said in a tearful videotaped statement played in court at Chaney’s sentencing in December 2012.

“That feeling of security can never be given back and there is no compensation that can restore the feeling one has from such a large invasion of privacy,” Aguilera wrote in a statement before Chaney’s sentencing.

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