Chinese facial-recognition companies are getting very, very good at what they do.

Locking 'em up: A police department in China went from capturing a handful of suspects a year with officers watching CCTV cameras to capturing 69 suspects in one month after deploying software made by the firm SenseTime.

Big data: Companies in China have access to a government trove of video surveillance footage that’s unmatched on the planet. Xu Li, CEO of SenseTime, told the Financial Times that his firm has processed 500 million faces and has a single client that needed 300 million faces verified.

But: China is leading the way in facial-recognition software and trying to become an AI powerhouse. But foreign governments won’t like the idea of their citizens’ data living on Chinese servers. Besides, American companies are hard at work on their own surveillance technology.