A provincial government spokesman yesterday denied reports that Gansu Vice-Governor Guo Kun was being investigated for graft. Chinese-language news portal Chinesenewsnet.com yesterday quoted a government source as saying Mr Guo, 59, was being 'shuang gui' - a procedure that requires a cadre to report to the party's graft investigators. The report alleged Mr Guo had conspired with an unidentified mistress in Hong Kong and received at least 2.7 million yuan (HK$2.55 million) in bribes. The spokesman said the allegation was a fabrication. Officials said Mr Guo had taken part in the Lanzhou Trade Fair, which closed on Saturday - a sign he was still politically active. However, a senior government source said Mr Guo, who is due to retire next year, was under investigation but it was not a serious case. He refused to give details. 'They [Mr Guo's concerns] are just small problems,' the source said.