The ruling Chinese Communist Party has issued orders to local officials and law enforcement banning the occurrence of any major crimes, including acts of terrorism or extreme acts of personal violence, and any mass gathering of people, including petitioners heading to Beijing to complain about the government.
The move comes as President Xi Jinping seeks to silence dissent ahead of the 19th Party Congress, consolidating his power as a "core" leader of the party in the tradition of late supreme leaders Mao Zedong and Deng Xiaoping.
An unsigned directive sent to neighborhood committees around the country identifies the three biggest threats to a successful Party Congress as any mass gathering of people "having nationwide impact," a terror attack, and any incident involving public safety.
The notice calls on local officials and security teams to "take strict steps to prevent any major event having a major impact on political stability."
Such events might include "mass incidents involving petitioners coming to Beijing," the notice said, in a reference to potential protests like those organized in recent months by thousands veterans of the People's Liberation Army outside government buildings in the capital.
Fire disasters involving large loss of life and injury or major transportation accidents are also cited as potential threats to stability, the notice warned.
Authorities across China must also be on the lookout for potential acts of terrorism or "individual extreme violence," the notice said.
Beijing-based democracy activist Zha Jianguo said the clampdown means close surveillance by state security police for any critics of the regime ahead of the Party Congress, which is expected in October.
"The 19th Party Congress is the biggest political event in mainland China this year, and therefore the most sensitive time of all," Zha said.
He said the state security police recently intervened to prevent around 10 of his friends from gathering in a Beijing restaurant to mark his birthday.
"They were stopped from coming, and they took me away [out of town]," Zha said. "They wouldn't allow me to be in Beijing on that day."
"During our 'chats' on that day, they mentioned the 19th Party Congress in October," he said. "The police asked me where I wanted to go on vacation during the 19th Party Congress."
Enforced 'vacations' for dissenters
China's state security police frequently use enforced "vacations" with dissidents and activists in out-of-town tourist destinations to prevent them from gathering at politically sensitive times.
The directive comes as authorities in the southwestern province of Yunnan detained a man on Sunday with the online nickname "Guanlan Tianxia" in Luoping county for social media tweets about Mao Zedong and Xi Jinping.
He was held for five days' administrative detention, which can be handed down to perceived troublemakers by police without the need for a trial, and released on Thursday, sources said.
"For the past couple of years, [people have been] held in administrative detention, criminal detention, or event sentenced to imprisonment because they dare to mention our emperor," a social media user who asked to remain anonymous told RFA.
"Wang Jiangfeng from Zhaoyuan was jailed for two years, while Li Tiantian and Ren Niejun from Shanghai were held under criminal detention," the social media user said. "All for criticizing our current emperor."
Last week, authorities in the southwestern region of Guangxi detained rights activist Tan Aijun after he boarded a bus to Hong Kong, preventing him from crossing the internal immigration border at Shenzhen.
Tan said he had been hoping to catch a plane to Thailand in a bid to flee continual official harassment at home, but was told he had been slapped with a travel ban because he was a "threat to national security."
"He took my documentation and just cut out [my travel permit]," Tan told RFA after the incident. "They wouldn't let me go through immigration, and they didn't give me a reason. I found out after I got home that I've been under this ban since last October."
And Sichuan rights activist Deng Chuanbin reported a similar ban after he tried to leave China along with his family.
"They told me that the police in Yibin, Sichuan, had canceled my travel permit," Deng said.
Reported by Qiao Long for RFA's Mandarin Service, and by Hai Nan for the Cantonese Service. Translated and edited by Luisetta Mudie.