Get breaking news alerts and special reports. The news and stories that matter, delivered weekday mornings.

The tweets and Facebook posts came flooding in: from actors and other celebrities, from women not normally in the spotlight, even from some men.

On Sunday night, after a tweet from actor Alyssa Milano, social media was inundated with personal stories of being the victims of sexual harassment or assault.

"Suggested by a friend: If all the women who have been sexually harassed or assaulted wrote 'Me too' as a status, we might give people a sense of the magnitude of the problem," Milano posted on Twitter.

If you’ve been sexually harassed or assaulted write ‘me too’ as a reply to this tweet. pic.twitter.com/k2oeCiUf9n — Alyssa Milano (@Alyssa_Milano) October 15, 2017

Get breaking news and insider analysis on the rapidly changing world of media and technology right to your inbox. This site is protected by recaptcha

#MeToo quickly rose to become a top trend, and still was as of Monday morning. Some, like fellow actors Anna Paquin and Debra Messing, simply tweeted "Me too." Others used the hashtag to share messages to victims: "It's never, ever your fault, and you're not alone," one woman wrote.

It's never, ever your fault and you're not alone. #MeToo — HeyItsDianeWalker (@DianeWalker101) October 16, 2017

The #MeToo movement comes in the wake of allegations of decades' worth of sexual misconduct by one of Hollywood's most powerful producers, Harvey Weinstein. Explosive reports in The New York Times and The New Yorker allege the film mogul lured women into hotel bars and rooms and harassed or assaulted them in what some have described as an open secret whispered about for years in Hollywood. Weinstein was fired from the company he co-founded with his brother but has denied "any allegations of non-consensual sex."

Related: NBC THINK: Weinstein Accusations Prove Women's Courage Is Contagious

The hashtag prompted by Milano also led men to come forward, either with their experiences of being harassed or in solidarity against inappropriate conduct.

"Men, Don't say you have a mother, a sister, a daughter... Say you have a father, a brother, a son who can do better. We all can. #MeToo," tweeted comedy writer Nick Jack Pappas.

Men,



Don't say you have a mother, a sister, a daughter...



Say you have a father, a brother, a son who can do better.



We all can.#MeToo — Nick Jack Pappas (@Pappiness) October 16, 2017

Milano co-starred in the series "Charmed" with Rose McGowan, who has accused Weinstein of raping her.

Related: Why Did Twitter Suspend Rose McGowan?

McGowan was briefly suspended from Twitter last week, prompting a different hashtag: #WomenBoycottTwitter. Twitter later said the suspension was due to McGowan tweeting out a private phone number.

In an essay last Monday, Milano explained that she was disturbed by the Weinstein allegations but "ecstatic" that it "opened up a dialogue around the continued sexual harassment, objectification and degradation of women."

"To the women who have suffered any form of abuse of power, I stand beside you. To the women who have come forward against a system that is designed to keep you silent, I stand in awe of you and appreciate you and your fortitude. It is not easy to disclose such experiences, especially in the public eye. Your strength will inspire others. Thank you, thank you, thank you, for fighting this battle so hopefully my daughter won't have to," she wrote.