A Japanese pop idol remains in critical condition after a knife attack by an alleged stalker, and police say a suspect arrested at the scene had been harassing the performer online.
Police say Tomohiro Iwazaki travelled more than 500 kilometers to kill the young woman he was infatuated with -- pop idol Mayu Tomita.
They say he admitted to stabbing her 20 times outside a venue where she was about to perform. He was then arrested at the scene.
Many are now asking, how could this happen?
The 20-year-old had been performing for about 4 years. She is one of countless pop idols in Japan, young performers and role models hired mainly because they are cute.
News of the attack shocked her fans.
"I cannot believe it. I just hope this is not real," one male fan said.
The initial police investigation has revealed that Iwazaki began attending Tomita's concerts around the start of the year. They believe he tried to find out her phone number and that he also sent her a watch as a gift.
Police say they believe Iwazaki sent more than 300 messages to Tomita's Twitter account over the course of 4 months. In that time, the messages that started out as nice became hostile.
According to police, Iwazaki said he got angry when the gift he sent was returned to him.
The attention from Iwazaki had turned scary. Tomita reported what was going on to the police. But they did not take preventative measures. They say they did not think the online harassment required action.
A counselor regularly consulted on stalking cases says police should have acted.
"Police should have contacted the alleged stalker," says Akiko Kobayakawa, who is director of Humanity NPO.
She also says they could have done more to educate Tomita about possible risks to her safety.
"I think police should have done more, such as advising her to find someone to take her to and from the venue or urging guards to be more vigilant," Kobayakawa says.
Tomita is not the first pop idol in Japan to be attacked. In 2014, 2 members of Japan's pop idol group AKB48 were slashed by a man with a saw at a fan event. The pair received serious injuries from the attack.
Kobayakawa says that social media has changed the relationships between celebrities and their fans in an alarming way.
"These days some can be delusional and believe that they have a relationship with the pop idol. That fuels their passion," she says. "And when they feel rejected, that can accumulate and turn into anger."
And don't think stalking is just a problem for pop idols.
Kobayakawa says she's getting more and more people telling her they have problems with online stalkers. And in order to stay safe, police have to work with those who are being harassed.