The Delhi Police said that DCW did not have permission to march towards the PMO but it later on ensured that the letters were submitted at the reception of the PMO.
The letters were addressed to Prime Minister Narendra Modi, and carried a demand for completion of trial in child rape cases within six months. The letters also demanded death penalty for the accused in rape cases.
Around 50 DCW volunteers and members were going towards Vijay Chowk in cars carrying banners, the police said.
"They did not have permission to go to the PMO. We also did not have any prior information about their arrival. They were stopped and requested to not proceed since Section 144 of the CrPC was imposed in the area and Parliament was in session.
"They were not ready to listen. They were asked to move in a bus and detained," Deputy Commissioner of Police (New Delhi) Madhur Verma said.
He said the Delhi Police ensured the submission of the letters.
While Ms Maliwal alleged that she sustained injuries, the police said that as per her medical examination carried out at the Lok Nayak Jai Prakash Narayan Hospital, no fresh external injuries were found.
The DCW had launched 'Rape Roko' campaign after the brutal rape of an eight-month-old baby in January.
Yesterday, male participants of the campaign walked the streets of the national capital wearing only boxer shorts to give the message that 'clothes do not cause rape, sick mentality does'.
"Lakhs of people sent their requests to the prime minister in form of letters with great hopes. This is their Mann Ki Baat. It is really sad that instead of respecting the will of the people, the letters were stepped upon and we were manhandled by the Delhi Police," Ms Maliwal claimed.
"Such acts shall not deter me or my team...I request our honorable prime minister to take immediate cognisance of these letters and ensure a strong system for giving death penalty to rapists of children within 6 months of the incident," she said.
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