The arrests come at a time when Beijing is eager to demonstrate that cracking down on economic crimes is a priority. They also highlight the intensity of the investigation surrounding Mr Huang, the founder of the Gome electronics group, who has not been seen since late November when reports of his arrest on suspicion of economic crimes began to circulate.

Zheng Shaodong, assistant minister of public security and director of the ministry's economic criminal investigation bureau, and Xiang Huaizhu, the bureau's deputy director, have been detained, the official Xinhua news agency reported yesterday, quoting ministry sources.

Mr Zheng may have attracted the ire of ministry colleagues by warning police, in a national teleconference last month, to be careful about using detention and other tough measures in criminal investigations involving company executives. He said, in his last public appearance, that arrest of executives should be the last resort for those investigating corporate crime because “it could disrupt business . . . and even cause social unrest in some cases”.