Kunming has banned bulk-buying of face masks and the sale of white T-shirts and has regulated photocopying in an effort to avoid another public protest after two demonstrations against a petrochemical plant had embarrassed the city's government.
The Yunnan provincial capital has also required those buying face masks to show personal identification. After news of that rule emerged on microblogs, Anning, a city under the administration of Kunming, apologised  and cancelled the requirement.
Many people wore facial masks to prevent identification when hundreds of marchers took to the streets of the southwestern Chinese city on May 16 to protest against a petrochemical project , which is set to be built in Anning.
Facial masks have also become a symbol of protest for those objecting to breakneck economic development affecting air quality in Kunming, a city known for its "everlasting spring".
As Anning backtracked on the ID requirement on Saturday, residents discovered more restrictions have been imposed in the wake of the last protest.
Following up on online reports, the Southern Metropolis Daily uncovered  a sales ban on white T-shirts in effect until at least the end of June. Many demonstrators wore white T-shirts bearing written slogans against the petrochemical plant.
The daily also said people who wanted to make photocopies at shops needed to register with their personal IDs in several parts of Kunming.
On May 20, four days after the street protest in Kunming, the city's department for economic development and industry held a meeting on orders by superior organs under the theme “Welcome the South Asia Expo by preserving stability", the Yunnan Info Daily reported.
According to the report, new measures had to be taken to try to make sure the international participants of the China-South Asia Expo, to be held in the city for the first time from June 6 to 10, would not be confronted by similar protests.
A day later, the ID requirement on face masks was imposed. The Kunming Daily, the city's government mouthpiece, also reported on guidelines, titled "Notice on new civilised behaviour to welcome the South Asia Expo", issued by the municipal government on that day.
"Protecting social stability is every urban residents responsibility and duty," the notice read. On Saturday, the Public Security Department held a public "live drill" parading riot police  in plainclothes and in full gear, police dogs and armed vehicles.