SEOUL (AFP) - When US video-game maker Riot Games held a highly anticipated League of Legends championship match in South Korea last year, about half the spectators in the packed arena were women.
Waving glow sticks and handmade banners to support a top player called "Faker", more than a thousand young women - some of them dressed as characters from the game - erupted in celebration when the 21-year-old and his team sealed a 3-0 victory.
While the pastime is traditionally seen as the preserve of young men, the number of female gamers in hyper-wired South Korea has grown rapidly in recent years.
But the South's US$4.2 billion (S$5.5 billion) gaming industry has been hit by allegations of sexism and censorship targeting female gamemakers, likened by some to a modern-day witchhunt.
South Korea is the world's sixth-biggest video game market, boasting 25 million players - half the population - and multiple TV channels dedicated to broadcasting eSports competitions.
About 65 per cent of South Korean women aged 10 to 65 play video games, according to state data, compared to 75 per cent of men, and mobile games attract more female players than male.
Women now account for 42 per cent of all gamers in the country, according to industry tracker Newzoo.
But female gamemakers account for less than a quarter of the male-dominated industry.
Despite its technological and economic advances, South Korea remains a patriarchal society in many respects, and behind the facade of the global game powerhouse lies a heavily male-oriented culture.
The latest row began when the chief executive officer of Seoul-based IMC Games launched a probe into whether a female employee harboured "anti-social ideology" after complaints about her personal activity on Twitter.
Ms Sung Hye Jin had followed several feminist groups and retweeted a post featuring a slang term describing sexist men.
Some of the industry's key clientele of young, male gamers demanded her sacking, calling her a "cancer-like creature" who "followed a dirty ideology".
Ms Sung apologised for the perceived offence, vowing to unfollow the groups in question.
"I am so sorry that my reckless behaviour caused such problems," she wrote on Twitter.
She kept her job after CEO Kim Hak Kyu decided her actions were "just a mistake but not a crime", but he assured customers he would "remain endlessly vigilant" to prevent a recurrence.
Rights groups and the country's top labour union have condemned the investigation.
"This misogynistic action...has left many women in shock and fear," the Korean Confederation of Trade Unions (KCTU) said in a statement.
The KCTU accused Mr Kim and many games companies of "thought policing" women workers.
Mr Kim has since apologised in turn for his actions as the row spirals.
The global game industry has been dogged by criticism over its treatment of women in both games and real life - encapsulated in the so-called "gamergate" controversy in the US in 2014.
Critics of the way women were depicted in games received death and rape threats, prompting calls to reform the industry's chauvinistic culture.
South Korea's own game sector has a history of sacking women labelled as supporters of Megalia, a controversial online feminist group accused by many gamers of ridiculing men.
In 2016, top gaming company Nexon gave in to pressure from users to sack a voice actress after she posted a photo of herself wearing a T-shirt sold by the group emblazoned: "Girls do not need a prince".
Another major developer, Smilegate, promised last month to remove images by female illustrators accused by gamers of being linked to the group for writing or retweeting posts about women's rights issues.
Many gamers monitor female developers to check whether any of their tweets, retweets or likes involve feminism, and file complaints to their employers with boycott threats, multiple industry sources told Agence France-Presse.
All of them refused to be named, fearful of consequences for their careers or a backlash against their employers.
"These gamers relentlessly attack whoever posts anything slightly related to women's rights issues, and label the person a Megalia supporter who should be sacked immediately," said one senior manager at an online game firm.
"Game sales could go down very quickly if we don't cave in," she added, saying many companies in the ultra-competitive industry end up removing accused staff.
The female CEO of one gaming company said that Nexon's move in 2016 had emboldened and convinced many gamers that they had a "right to witchhunt" female developers.
Many workers now take extra caution on social media and avoid posting "anything remotely related to women's rights issues", she said.
"It's common sense that one should not be punished at the workplace for personal beliefs that have nothing to do with work," said the CEO.
"But that common sense is not accepted at all in this industry right now, especially for women."