Two protesters penetrated massive security around President Jiang Zemin yesterday, marring a huge police operation intended to keep human rights activists far from view during his visit. A middle-aged demonstrator shouted 'Free Tibet' as he sprinted towards a limousine carrying Mr Jiang towards the Millennium Dome. Dave Wetton, who appeared to have dodged heavy security by donning a worker's helmet and jacket to pass as a construction worker at the almost-completed dome site, was seized by police a metre from the vehicle and dragged away. Later, a Tibetan student at London University who gave his name as Jamphon, managed to break through police lines on a bicycle and unfurled a Tibetan flag in front of Mr Jiang's motorcade. He pulled the flag from under his jacket and shouted 'Free Tibet' before being forced off the road by a police motorcyclist, pinned to the ground by three officers and arrested. Mr Jiang shook his head as the motorcade sped away down the Strand in central London to attend a reception for the Bank of China at the Savoy Hotel. Earlier, Mr Jiang sailed down the River Thames aboard a launch flying a Chinese national flag to Greenwich Observatory, not far from the dome. As he stepped ashore, a small crowd of demonstrators who had gathered about 70 metres away began hooting horns, chanting 'Free Tibet' and waving the Tibetan flag. The President chose to look the other way as he walked to his limousine. Protesters also dogged Mr Jiang when he arrived at the dome. 'He looked pretty appalled by how close we had got to him but did not acknowledge our protests,' dissident leader Wei Jingsheng said.