Disciplinary staff in Wuhan, the provincial capital of Hubei in central China, were going about their routine workday when a red alert landed. It came from a large data model that flagged a possible case of corruption.

The alert said a company had taken on more than 10 projects this year. Its registered capital had been reduced from 50 million yuan (US$7.5 million) to 10 million yuan, yet its paid-in capital remained at zero. Moreover, more than 80 per cent of the projects it took were residential communities.S1S2