A Japanese television network yesterday called in doctors, psychologists and animation experts to find out why a cartoon based on a video game, Pocket Monsters, triggered convulsions among hundreds of children nationwide.
TV Tokyo programming division manager, Mr Hironari Mori, said more than 700 people, mainly children, were rushed to hospitals after watching the programme on Tuesday night.
The Home Affairs Ministry said 208 people, aged from three upwards, including a man aged 58, were still in hospital with epilepsy-type symptoms more than 24 hours after the showing.
"We are investigating the cause of the incident using outside experts," Mr Mori said.
The seizures began about 20 minutes into the 30-minute programme, which is broadcast on Tuesdays at 6.30 p.m.
The blame was put on a scene depicting an explosion followed by five seconds of flashing red lights from the eyes of the most popular character, "Pikachu", a rat-like creature.
The episode featured characters entering a computer to fight each other. The explosion was set off by a "vaccine bomb" detonated to destroy a computer virus.
Even the Japanese Prime Minister, Mr Ryutaro Hashimoto, was drawn into the national debate, which dominated news headlines through the day.
Commenting on the cartoon's fascination with ray guns and laser beams, Mr Hashimoto said their portrayal should be carefully considered because they were "weapons".
Mr Mori said the offending section passed inspection before broadcast, but in hindsight "we believe there may have been problems with presentation and production technique".
TV Tokyo imposed a health warning on future episodes, telling viewers that watching Tuesday's instalment of Pocket Monsters could cause fainting and nausea.
"I must say that as an adult that part made me blink, so for a child the effect must have been considerable," Mr Mori said.