Condemning the incident as the "worst" day in the history of India, Modi said "the PM had said during the elections that he would bring back black money stashed in Swiss banks within 100 days of coming into power. But today, it is two years and nothing has happened".
Modi, who was inaugurating a new dental college here, said "Congress will have to answer 120 crore people of India about the use of violence on innocent people".
"I would like to tell Prime Minister Manmohan Singh that you cannot escape by saying that you did not know. You are directly responsible for what has happened at the Ramlila ground in Delhi," Modi said.
"The lathi-charge on innocent people has been at your (Manmohan Singh) behest on behalf of the Delhi sultanate and not by the Sheila Dixit Government," Modi said.
He said the lathi-charge by police while people were sleep, was "Ravanlila at Ramlila ground."
The police first attacked people in their sleep and then took away Baba Ramdev and did not disclose where he has been taken, Modi said adding "even the US after killing (Osama Bin) Laden had revealed to the world what they had done in two hours."
"The Delhi sultanate is bound on suppressing the voice against corruption," he added.
Modi said the government''s action against Baba Ramdev reminded him of the days of the Emergency, which too coincidently was in the month of June in 1975.
"The intervening night of June 4-5 is the beginning of the end of the Delhi Sultanate," he warned.