The images were posted to a 4chan forum, and they were soon shared on Imgur and Reddit.

The 4chan user claims to have more than 60 nude photos of Lawrence alone, as well as an explicit video of the actor.

A spokesperson for Lawrence confirmed the authenticity of the photos, and told BuzzFeed they were not going to let this violation of privacy go unpunished.

"This is a flagrant violation of privacy. The authorities have been contacted and will prosecute anyone who posts the stolen photos of Jennifer Lawrence," the publicist said.

Upton's publicist also told the website they were "looking into this".

A master list supposedly containing the names of all the hacked celebrities has also been doing the rounds online, and includes Upton, Amber Heard, Victoria Justice and Mary Winstead.

According to BuzzFeed, the hacker accessed the photos thanks to an iCloud leak that allowed the celebrities' phones to be hacked.

The anonymous poster was also asking to be paid in bitcoin for the release of the Lawrence video.

Victoria Justice was quick to jump on Twitter and hose down the rumours.

"These so called nudes of me are FAKE people. Let me nip this in the bud right now. *pun intended*," Justice tweeted.

Actor Mary Winstead, however, confirmed the photos of her were real, and expressed her disappointment 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," she tweeted. "Knowing those photos were deleted long ago, I can only imagine the creepy effort that went into this. Feeling for everyone who got hacked.

"You know what's better then leaked nudes? Earning the trust and respect of another human to the point that they share their body with you."

Other celebrities affected have yet to comment, and for now the rest of the photos are unverified.

According to Inquisitr, authorities in the United States have been cracking down on people who leak stolen photos of celebrities.