On Saturday, thousands of women in red, black, and white gathered together in Seoul for what many consider the largest women-led protest ever in South Korean history. Shielding their faces with masks to protect themselves from harassment or online trolling, the protesters aimed to raise awareness of the country’s widespread problem of molka, or hidden spy cam pornography, in which women are secretly recorded while using public restrooms, riding subway escalators, and even sitting at their desks.

As one protester’s sign read, “My life is not your porn.” Another banner read (translated from Korean): “Wanna shit with my guard down.” Several women also shaved their heads in protest of the government’s failure to protect them.

“The fear that women feel toward spy cameras isn’t out of proportion; it’s rational,” said Chang Dahye, a researcher at the Korea Institute of Criminology, in an interview with Korea Exposé. “It’s not just footage of sexual intercourse. There [is] spycam footage of women relieving themselves in toilets; photos of women in bikinis, at home, walking on the street. On a website called Soranet, men would upload photographs of their girlfriends or wives, and ask others to rate the women’s genitals.”

It’s such a huge problem that Seoul has an all-women “hidden camera-hunting” squad to check public restrooms for the tiny devices. “It’s my job to make sure there’s no camera to film women while they relieve themselves,” one squad member told the South China Morning Post last year. “It’s weird that there are people who want to see something like that ... but this is necessary to help women feel safe.”

In December 2013, the government rolled out another, albeit controversial, effort to help quell the trend: The Korea Elevator Safety Institute distributed signs warning women to “Please cover your skirt” as they rode up subway escalators. Many pointed out the message put the onus on women to protect themselves instead of admonishing perpetrators, and the text was later changed. According to the Korea Times, sex crimes on trains rose 84 percent between 2012 and 2014; half of those cases occurred on subways.

After more than 200,000 people signed a national online petition asking the government to ban spycam sales and enforce stricter punishments for people caught filming illegally (most are settled by fines), the Ministry of Gender Equality and Family launched a new initiative in May to offer victims of digital sex crimes—including revenge porn and upskirting photos, support services—including counseling, help getting photos found online deleted, litigation support, and more. “If you experience any digital sexual crime, the government is here to help,” a statement read.

But, as writer Yeji Lee pointed out in a 2016 article for 10 Magazine, many critics have questioned the effectiveness of the ministry in making lasting change. “The real problem with attempts at alleviating gender inequality in South Korea,” Lee wrote, “is that they have been largely ineffective, half-hearted attempts that do more to try and improve a single politician’s public image than actually introduce policies that would create an equal environment that would be beneficial for both genders.”

Moreover, protesters at Saturday’s march pointed out that in order to fix the epidemic of molka crimes, institutional sexism also needed to be addressed. (“Innocent if you have a dick, guilty if you don’t,” one of the rally’s speakers yelled. “Is being a man a privilege in itself?”) In May, a woman was quickly arrested after police determined she had photographed a nude male model (a colleague of hers) and posted the image online without his consent. The response was in stark contrast to what many women who are victims of similar crimes experience.

Katharine Moon is a gender and women's rights expert with a focus on South Korea who teaches at Wellesley College. She says that the epidemic of spycam schemes may be connected to how men have dealt with the educational, economic, social, and political advances South Korean women have made in the last two decades—though the uptick in upskirting and illegal filming is fairly recent. According to a recent study by the Korean Women Lawyers Association, about a quarter of all sex crimes that were reported in 2015 involved these kinds of spycams. “And that is a really large increase when you compare it to in 2006, when about 3.6 percent of the total number of sex crimes reported involved spycams,” Moon says.

This new power dynamic, coupled with economic difficulties that have led to “a social, psychological crisis” for young people, she continues, may have created conditions that allowed insecurity to thrive and fester. A spy cam scheme may be a “more passive rather than aggressive way to act out their masculine insecurities and their social economic discontent on women,” she says. “There are a lot of men in Korea, especially in the younger generations, who blame women for some of the problems that they face. There’s a sense of rejection by women and also being bested by women in schools and in jobs.”