Chinese police prevented journalists filming the scene on Wednesday
A group of protesters who tried to unfurl a pro-Tibet banner near an Olympics venue in the Chinese capital Beijing have been held by police.
A British journalist who was in the area covering the protest is also reported to have been arrested.
The journalist has been identified as John Ray of ITV News.
This is not the first protest to happen during the Olympics. A man was removed from an equestrian event on Saturday for trying to unveil a Tibetan flag.
Up to eight protesters, from the group Students for a Free Tibet, had tried to hang a banner in the Chinese Ethnic Culture Park near the National Stadium reading "Free Tibet".
But they were arrested within seconds of the attempt.
John Ray of ITN being arrested
Mr Ray was also briefly detained, and claims he was dragged into a nearby restaurant and forcibly held down by officers. "I tried to explain to them that I was a British journalist but they would not even let me take out my identification documents," Mr Ray told reporters.
This was an assault in my mind. I am incredibly angry about this
John Ray ITN China correspondent
"I have been roughed up. They dragged me, pulled me and knocked me to the ground. Now they are filming me," Mr Ray told the UK's Guardian newspaper from the back of the police van as he was driven away.
Mr Ray later told AFP news agency he had been held for about 20 minutes. The agency quoted the reporter and witnesses as saying that police officers had stamped on his hands while inside the restaurant.
Mr Ray was then released, but says his equipment bag was confiscated.
"This was an assault in my mind. I am incredibly angry about this," he told AFP.
The agency said the journalist's shoes were scuffed, his trousers and shirt dirty and some bruising was visible on his hand.
The fate of the other detained protesters was not clear.
China pledged to allow freedom for journalists covering the Games, but has since been criticised for trying to curtail coverage of sensitive subjects all the same.
This was probably the largest in a string of recent protests in Beijing to coincide with the Olympics.
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