In Tamil Nadu these days, any unflattering remark about a film star seems to anger their fans. Last week, Kasturi Shankar found herself in the line of fire for tweeting a sarcastic dig about fellow actor Ajith and his fans. It all started with Kasturi wishing another actor, Rajnikanth, for his birthday on December 12 and drawing insults from Ajith’s fans. She responded by calling them “Thala Vali”, meaning headache. Ajith is popular among his fans as Thala, or head. For this, she received a torrent of abuse on social media, even a video message from self-declared Ajith fans threatening her with “dire consequences” if she did not apologise publicly.

If this was not enough, Ajith’s fans blamed Kasturi for bringing the relentless trolling upon herself. “It was her fault,” one of the fans told Scroll.in, asking not to be identified for fear of legal action. “She shouldn’t be commenting about Ajith’s fans just to be in the limelight.”

Kasturi’s followers, the “Kasturi Army” as they call themselves online, responded in kind. “Let’s raise our hands against the haters #DirtyAjithFans,” many of them tweeted. “We love and support @KasthuriShankar.”

This is not exactly a new phenomenon. In August 2017, Dhanya Rajendran, editor of The News Minute website, was the target of rape threats from actor Vijay’s fans. She was reportedly bombarded with nearly 45,000 hateful tweets in just three days for casually remarking that after watching Shah Rukh Khan’s When Harry Met Sejal, she had felt it was worse than Vijay’s film Sura. The police later booked four unidentified people for threatening and abusing her.

Is this kind of trolling unorganised? Definitely, not. Tweet was sent before 6 pm asking me to wait. And they started the hashtag at 6 pm pic.twitter.com/lwpYYQmyRM — Dhanya Rajendran (@dhanyarajendran) August 7, 2017

Fans of Vijay and Ajith are particularly notorious for trolling. They also often abuse each other’s idols on Twitter and Facebook, and have started posting videos on YouTube mocking each other. Any remark against either actor invariably ends up in a Twitter war. This seems to have happened in the case of Kasturi as well. “There is a Twitter war between us and Vijay’s fans,” said the Ajith fan. “And Kasturi’s remarks provided fodder for them to troll us more.”

Despite their antagonism, the two sets of fans bandied together in March to troll actor Siddharth for speaking about the Tamil Nadu Film Producers Council’s decision to allow certain films permission to shoot during a strike. The council had called for a complete shutdown but allowed four films to continue shooting, including Vijay’s Thalapathy 62.

They are particularly vicious to women, subjecting them to a barrage of obscene and sexist remarks.

Commentators argue that this “trolling culture” is partly due to fan clubs being essential to the financial security of the Tamil film industry. This makes actors and producers wary of antagonising their supporters.

“Everyone is getting trolled now,” said the producer and columnist Dhananjayan Govind. “Sometimes it is best not to post tweets that might attract trolling. Ajith and Vijay have thousands of fans and it is not possible to expect the actors to rein in them all.”