Well-known top seiyuu Hirano Aya, known for her roles as Haruhi in The Melancholy of Haruhi Suzumiya, Konata in Lucky Star, etc., made an appearance on the Fuji TV program Gout Temps Nouveau where the young idol's love life became a topic of discussion. Speaking of her experiences in past relationships, it was a grave subject for an idol to talk about so openly, and unsurprisingly, fans' reactions weren't positive.

Fans became enraged in front of their TVs and took to 2ch, where they wrote abusive messages towards Hirano and, allegedly, even began planning her death. As Hirano herself had never said in front of her fans that she'd been in a relationship until now, amongst her core zealous fanbase, the majority seemed certain that she'd never had a boyfriend. Therefore, the appearance on this program was the very first time Hirano had ever spoken of any such romance like those she described, and the fans' rage in response to having watched the program was uncontrollable.

Even though it was merely the ordinary girl's talk commonly seen on and expected from Gout Temps Nouveau, Hirano's fans, who had truly believed in her supposed lack of a boyfriend, were full of tearful, anguished comments. Not stopping at just those, however, their outrage spiraled out of control as some users began planning for the assassination of their former idol, one comment reading, "I'm glad I didn't record [the program]; I'm going to kill Hirano Aya." Even on the seiyuu's Wikipedia page, a string of characters reading "die" was written approximately 67,000 times (as of now, the article has been restored to its original form). Meanwhile, in a slightly less extreme reaction, fans in possession of her CDs and posters have been destroying them and uploading pictures of the ruined merchandise to the Internet. This upset towards Hirano seems like it won't die down for a very long while.

Source is from here or so, and also includes some of the photos fans uL.

Voice Actress Haruna Ikezawa's Stalker Found Guilty
posted on 2010-08-10 09:13 EDT

Hiroshi Sasaki gets suspended term for defamation, multiple emails asking for personal meeting
Tokyo District Court's Tachikawa Branch found 28-year-old Hiroshi Sasaki guilty of stalking voice actress Haruna Ikezawa (Sgt. Frog, Futari wa Pretty Cure, Maria Watches Over Us) and gave him a suspended sentence on Tuesday. The unemployed Morioka City man was charged with defamation and violations of Japan's anti-stalking law for defaming Ikezawa on her homepage's bulletin board system and sending email messages requesting a personal meeting.

Sasaki received a 18-month sentence, but it was suspended for five years. If Sasaki does not break the law during those five years, he will not actually have to serve prison time. The prosecution had asked for an 18-month sentence without suspension. In his sentencing, Judge Haremitsu Mōri said that Sasaki did not worry about the trouble he caused the victim with his relentless messages, and the judge added that it was a "selfish, despicable crime."

From February to April of 2009, the suspect sent 16 mobile phone email messages that said, among other things, "Come by yourself to Morioka, since it's only two hours by shinkansen ('bullet train')." Ikezawa revealed on her official website in February of 2009 that she has an restraining order against a stalker who she did not name at the time.

Source: Sports Nippon