(CNN) Three human rights activists unfurled a banner reading "No Genocide Games" and a Tibetan flag at the flame-lighting ceremony for the 2022 Beijing Winter Olympics on Monday.
The ceremony -- which takes place in ancient Olympia, the birthplace of the ancient Olympics -- was attended by International Olympic Committee (IOC) president Thomas Bach, Greek President Katerina Sakellaropoulou and a number of dignitaries.
The three activists managed to enter the heavily policed archaeological site of the ancient stadium and attempted to reach the temple of Hera while the ceremony was being widely televised.
They succeeded in unfurling the banner meters from the temple, waving the Tibetan flag and calling for a boycott of the Beijing 2022 Winter Olympics before being stopped by police.
The Games must be respected as "politically neutral ground," said IOC President Thomas Bach during his speech in ancient Olympia.
"The Olympic Games cannot address all the challenges in our world. But they set an example for a world where everyone respects the same rules and one another," he added.
On Sunday, Greek police detained three protestors in Athens after they unfurled a banner opposing the Beijing 2022 Winter Olympics at the Acropolis archaeological site.
"Specifically, after entering the space, they approached the monument of Agrippa and tried to unfurl a large banner and two flags with ideograms and words in English," a Greek police statement said.
"Their attempt was not successful after they were noticed by the guard of the archaeological space who prevented them. They were subsequently arrested by police."
A trial has been set to take place in January, Greek police spokesperson Apostolos Skrekas said.
Two of the activists who were detained were Tsela Zoksang, an 18-year-old Tibetan-American activist, and 22-year-old Joey Siu, an exiled Hong Kong activist, the group 'Students for a Free Tibet,' said in a written statement. The activists have been released and are permitted to leave the country, the group said.
According to 'Students for a Free Tibet,' Zoksang and Siu are members of the 'No Beijing 2022' campaign, which "is demanding the International Olympic Committee (IOC) reverse its mistake in awarding Beijing the honor of hosting the Winter Olympic Games in 2022."
The group said in its statement that the IOC had "repeatedly ignored the evidence of the egregious human rights abuses by China, including a genocide of the Uyghur people, the brutal and illegal occupation of Tibet, and the severe and worsening crackdown against freedom and democracy in Hong Kong."
Human rights protests had also broken out during the lighting ceremony of the 2008 Beijing Olympics.
The Chinese capital will become the first city to host both the Summer and Winter Games with events scheduled to take place from February 4-20, 2022.