Beijing--Four protesters, two Americans and two British, were ordered to leave the site when they tried to hang pro-Tibetan independence flags onto a lamppost near the Beichen Bridge, meters away from the Nation Stadium early Wednesday morning, said BOCOG spokesman Sun Weide.

Pedestrians noticed the four protesters, three men and one woman, at 5 a.m. and called the police immediately, said Sun.

The four gathered at the Beichen Overpass near the National Stadium, or Bird's Nest. Two men climbed up two electricity poles to display the banners, said the police.

One banner was written with large black letters "One World One Dream Free Tibet" and another banner read "Tibet will be free".

The police rushed to the scene 12 minutes later and took them away for investigation.

The four have entered China on tourist visas, police said.

The Olympics is an sports gathering, said the spokesman in a press conference at the MPC.

"We object any kind of act that violates the Chinese laws," he told reporters.

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