China has sealed off Tiananmen Square, as part of a tight security blanket thrown around Beijing for President Bush's visit to China.
Large numbers of police cleared people from the square early Thursday and set up roadblocks around the St. Regis Hotel, where the U.S. delegation is staying.
Last week, more than 40 foreign followers of the banned Falun Gong spiritual movement caused chaos in Tiananmen Square as they staged a brief protest.
The protesters, including some two dozen Americans, were detained by police and subsequently expelled from China.
Washington has lodged a formal diplomatic protest over the alleged mistreatment of Americans.