Beijing has strengthened its security measures at Tian'anmen Square as the number of visitors increases.

    Security checkpoints have been set up at each underground entrance to the square and "all visitors will have to pass through them", Jia Yingting, deputy director of the Tian'anmen Square management committee, told a news briefing yesterday.

    Bags must be opened for checks and goods that may harm public security such as explosives, guns, knives, drugs and pornographic materials, are banned, he said.

    The square is now open to the public till midnight, but access to it may be temporarily limited during the Games when large cultural and sports activities are held there, he said.

    Numerous cultural and sports shows will be held in the square before and during the Olympics, includes performances by domestic and foreign college and middle school orchestras from Aug 1-3 and daily mass sports activities from 7 am to 9 am from Aug 4-14, Jia said.

    There will also be a promotion of China's intangible cultural heritage on Aug 15, 18 and 22.

    Security measures could be further strengthened if the number of visitors to the square keeps growing, he said.

    Other emergency plans have been drawn up, and authorities are confident of maintaining good order during the Games, he said.

    Meanwhile, authorities said on Tuesday that