Police officers work in front of the building of the Royal Exchange in London March 31, 2009. A suspected package was found near the building of the Royal Exchange on Tuesday. Police sealed off the area, but shortly afterwards an all clear order was given. London police have tightened security for the summit of the Group of 20 Countries to protect the meeting from possible violent protests. [Xinhua]

Workers place battens around a war memorial statue outside the building of the Royal Exchange in London March 31, 2009. The British capital is bracing for protests before and during the summit of the Group of 20 Countries, to be held on April 2.[Xinhua]