Janata Dal (United) chief Sharad Yadav was one of those seen getting out of his car and wading through the protesters to reach a secured area. As precautionary measure, the police brought in water cannon.
The Sikh demonstrators were protesting against the acquittal of Congress leader Sajjan Kumar in a 1984 anti-Sikh riots case last week.
The protesters later courted arrest following which the cops cleared the area. They were taken to the Parliament Street Police Station.
The police had barricaded the area, which also houses the President's residence, Rashtrapati Bhawan, and important ministries, including the Prime Minister's Office in the North and South Blocks.
There have been protests by Sikh groups every day since May 1, when a trial court acquitted Sajjan Kumar, a former Delhi MP, of all charges in one of three riots cases against him. In this case he was accused of murder and of instigating a riotous mob that killed five Sikhs in Delhi's cantonment area on November 2, 1984.
Yesterday, the protesters had tried to march towards Prime Minister's residence, but were stopped at Parliament Street as they left Jantar Mantar. The leaders of the Sikh protesters were detained at the Parliament Street Police Station.
Many Sikh protesters shouted slogans against Congress president Sonia Gandhi as they held protest outside her home last Thursday. She was away to Karnataka to campaign for the state elections.
The protesters say they will not stop their street protests till the Central Bureau of Investigation (CBI), which prosecuted the case, appeals against the verdict in a higher court. The CBI has not decided on its course of action yet.