China’s ambition to collect a staggering amount of personal data from everyday citizens is more expansive than previously known, a Times investigation has found. Phone-tracking devices are now everywhere. The police are creating some of the largest DNA databases in the world. And the authorities are building upon facial recognition technology to collect voice prints from the general public.

The Times’s Visual Investigations team and reporters in Asia spent over a year analyzing more than a hundred thousand government bidding documents. They call for companies to bid on the contracts to provide surveillance technology, and include product requirements and budget size, and sometimes describe at length the strategic thinking behind the purchases. Chinese laws stipulate that agencies must keep records of bids and make them public, but in reality the documents are scattered across hard-to-search web pages that are often taken down quickly without notice. ChinaFile, a digital magazine published by the Asia Society, collected the bids and shared them exclusively with The Times.