Crank calling is so rampant in Taiwan that even the president and vice-president have been victims. Some of the calls have been flirtatious or erotic, prompting concern from the authorities at how easy it has been for crank callers to get through to the leaders' mobile phones, Taiwanese media reported yesterday. According to the pro-government Formosa TV news channel, President Chen Shui-bian received a mobile phone call several weeks ago from a woman with a mainland accent asking whether he had ever bought tickets for Hong Kong's Mark Six lottery. A perplexed Mr Chen hung up, wondering how his secret mobile phone number had been leaked, FTV said. Cable news network TVBS reported that Mr Chen and his deputy, Annette Lu Hsiu-lien, had received flirtatious text messages and had ordered security authorities to do something to stop the harassment. Presidential Office secretary-general Mark Chen Tan-sun declined to reveal whether the two had been victimised by crank calls. 'There is a need for the security authorities to look into this issue ... if such things have happened.' TVBS warned of the risk of eavesdropping by mainland intelligence services, saying the crank calls suggested the leaders' mobile phone numbers had been leaked and could be tapped. But security and presidential officials said the callers merely dialled the numbers randomly in the same way most fraud rings in Taiwan operated.