China's Communist Party will hold a four-day meeting to discuss a historical resolution that would help enhance the authority of President Xi Jinping.
The sixth plenary session of the Central Committee will open on Monday in Beijing. President Xi and other top leaders will attend the gathering, together with more than 300 officials.
Police personnel and vehicles were deployed around a military-run facility on Sunday, where the meeting is believed to be held.
During the session, President Xi and other leaders will form key policies and make personnel decisions. They will also deliberate on a key resolution aimed at comprehensively reviewing the history of the Communist Party.
Such resolutions have been adopted only twice, in 1945 and 1981. Experts say the resolutions helped former leaders Mao Zedong and Deng Xiaoping consolidate their power.
This year marks the 100th anniversary of the party's founding. The latest move is seen as an attempt by the current leadership to set the stage for President Xi to be re-elected at the party's congress next year, for a rare third term.