Climate activist Sonam Wangchuk and 20 other protestors were detained by the Delhi Police for protesting outside the Ladakh Bhawan here on Sunday, officials said.
Around 20 to 25 protesters, who were on fast with Wangchuk, were detained and taken to the Mandir Marg police station, they said.
Heavy police deployment was arranged to maintain the law and order.
Some of the protesters argued that they were not protesting, but sitting peacefully.
A senior police officer said the protesters do not have any permission to sit outside the Ladakh Bhawan.
"They have filed an application to hold protest at the Jantar Mantar. Their application is under consideration. They are not allowed to protest at any other site. We have detained a few people, who will be released soon," he said.
Wangchuk, along with his supporters, marched to Delhi from Leh demanding Ladakh's inclusion in the sixth schedule of the Constitution.
They were detained at the capital's Singhu border earlier on September 30 by the Delhi Police and released on the night of October 2.
The group is demanding a meeting with top leaders, including Prime Minister Narendra Modi.
The sixth schedule of the Constitution includes provisions for the administration of tribal areas in the northeastern states of Assam, Meghalaya, Tripura and Mizoram.
It establishes autonomous councils that have legislative, judicial, executive and financial powers to independently govern these areas.
The protesters are also demanding statehood, a public service commission for Ladakh and separate Lok Sabha seats for Leh and Kargil districts.
