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Two British campaigners arrested in Beijing after staging a Free Tibet protest outside the Olympic Stadium have arrived back in Britain vowing that further demonstrations would take place during the Games.

Iain Thom, 24, who unfurled a banner reading "One World, One Dream, Free Tibet" after climbing a 120ft pylon, and Lucy Fairbrother, 23, who co-ordinated the protest on the ground, were greeted by cheering supporters at London City Airport after they were deported from China.

Miss Fairbrother, a graduate of Bristol University whose father is a former bursar of Trinity College, Cambridge said: “We are only a very small part of this campaign and the ongoing struggle.

“We will carry on fighting and there will be more protests during the Olympic Games. Despite what we have done the situation in Tibet is still dire."

She said that the Chinese police had treated them well, contrasting this with the authorities' crackdown in Tibet. "We were treated very even-handedly, we were questioned but the police were kind to us. We were taken immediately to a police station and questioned.

"One of the reasons that we were there was that Tibetans couldn’t be there in our place. They were refused visas and if anyone in Tibet dared to protest, they would certainly be treated much more harshly and would face torture and imprisonment.”

She said she had feared spending time in jail, but had "made friends" with the policemen who arrested her.

“We were perhaps saved by the incredible PR strategy surrounding these Olympics. After our arrests we were going into the complete unknown but in fact we made friends with the officers. We ate with them, we talked about their families and we asked about their lives in Beijing."

Mr Thom, from Edinburgh, said that a long interest in climbing and years of preparation explained the success of the protest. He said he had practiced by climbing trees near his home, and had had no trouble evading the 110,000 security personnel deployed across the Chinese capital.

“It was not difficult to get through the security as we had been planning this for four years."

He described how they were arrested after staging the protest out the showpiece stadium at dawn yesterday.

"I was up there for about an hour - it seemed longer. There was a fire truck to bring me down safely," he said

“We knew there were risks involved but the risks were nothing compared to the suffering Tibetans have endured. Security was tight but we walked up to the pole – and everything was done in a straightforward manner. We were arrested for disturbing public order and were later escorted to the airport."

He added: "We wanted to make a call to world leaders and the Chinese government for meaningful change – this is a matter of basic human rights.

“It was definitely all worth it but expect there to be more. The job is not done but we feel like we have achieved something.”

The pair were put on a flight from Beijing last night after they were arrested yesterday along with Tirian Mink, 32, from Portland, Oregon, and Phill Bartell, 34, from New Jersey, who unfurled a banner from a second pylon

Miss Fairbrother's mother Linda, 58, a broadcast journalist, met her daughter at the airport along with members of the Students for a Free Tibet campaign group, who waved Tibetan flags and white Tibetan scarves.

After embracing her daughter, Mrs Fairbrother said: “I have done live TV all my life but I haven’t been that nervous since my school exams. It is wonderful to have her back.”