Beijing authorities have been rounding up activists and dissidents as usual ahead of the annual meetings of the National People's Congress and Chinese People's Political Consultative Conference, which begin this week.
But the atmosphere in the capital is even more tense than usual for this time of the year, with recent uprisings in the Middle East and North Africa having struck a raw nerve.
Dissidents and activist lawyers in Beijing said controls had tightened since last week. Some were stopped from visiting sensitive areas such as the Wangfujing shopping street or Xidan business district - locations specified in calls for 'jasmine rallies'.
The call for rallies, inspired by 'jasmine revolutions' in the Arab world, coincided with security preparations for the annual meeting of the CPPCC, beginning tomorrow, and the NPC, starting on Saturday.
'Two days ago, police officers visited my office and home to remind me that the two meetings are approaching, and not to visit any sensitive places to make trouble,' activist lawyer Mo Shaoping said. 'I know they were reminding me not to take part in the Sunday rallies.'
Zhang Xianling, the mother of a student killed in the 1989 Tiananmen Square crackdown, said she had been under surveillance since February 19, the day before the first round of Sunday rallies.