About 100 protesting Tibetan exiles tried to breach a security cordon around the Chinese Embassy in New Delhi on Wednesday, a day ahead of the Beijing Olympics torch run in the Capital.
They were pushed back by Indian police, and about two dozen were arrested and taken away in police vans.
Another 50 were forced back onto the buses in which they had arrived. It was not immediately clear whether they were being arrested or detained.
The protesters, some of whom were carrying Tibetan flags, chanted "We want freedom, we want justice" and spray-painted "No Olympics in China" on a street near the embassy.
Police say more than 5,000 policemen have already been deployed to prevent chaotic protests during the torch run Thursday like those held by Tibetan independence supporters in London and Paris.