Chinese police have admitted to wrongly shaming a famous businesswoman after a facial recognition system designed to catch jaywalkers mistook an advert on the side of a bus for her actual face.

Dong Mingzhu, president of Chian's biggest air conditioning maker, had her image flashed up on a public display screen in the city of Ningbo, near Shanghai, with a caption saying she had illegally crossed the street on a red light.

But Ningbo's facial recognition cameras had actually only caught an advert featuring her face on the side of a passing bus – a fact quickly spotted by Chinese citizens, who shared pictures of the alert on Weibo, a social network similar to Twitter.

On Wednesday, Ningbo traffic police admitted their mistake, saying the alert had been "immediately deleted afterwards" and that technicians had "completely upgraded the system to reduce the false recognition rate".

The incident highlights China's growing use of automated systems such as facial recognition cameras to catch petty criminals, as well as in a campaign of repression against Muslim citizens in the western province of Xinjiang.