SHANGHAI (REUTERS) - Authorities have punished five officials in China's Zhengzhou city for deliberately turning thousands of citizens' health codes red, the local anti-corruption authority said in a statement published late on Wednesday (June 22).

The local government announcement comes after depositors of small rural banks in Henan province, where Zhengzhou is located, publicly alleged that their health codes abruptly changed from green to red when they began to travel to Henan to protest blocked withdrawals.

Their case has sparked widespread public interest in China.

Since the start of Covid-19, localities across the country have used colour-marked health codes to grant individuals access to public transportation, hotels, and other basic amenities, using location trackers and other data to assess one's exposure to the virus.

Earlier this month, hundreds of aggrieved depositors on their way to Henan reported their health codes suddenly turned red, sparking concerns about government abuse of the health code system across the country.

According to Wednesday's official statement, Feng Xianbin and Zhang Linlin, two officials from the city's epidemic and control headquarters, "decided without authorisation" to grant red codes to the aggrieved depositors travelling to Henan.

Three other officials subsequently acted on Feng and Zhang's orders.

As punishment, Feng was stripped of his party credentials, while the other officials were slapped with demerits, the statement quoted authorities as saying.

In total, 1,317 individual depositors saw their codes turn red due to Feng and Feng's cohorts' actions.

The officials "severely damaged the seriousness of the regulations governing the use of health codes," the authorities said.