People started gathering at Jantar Mantar here at around 10 AM and sat in silence.
Aam Aadmi Party leaders Arvind Kejriwal, Manish Sisodia and Kumar Vishwas also joined the protest along with some of their supporters with their mouth tied with black cloth.
Aam Aadmi Party National Convenor Arvind Kejriwal tweeted, "her death is a matter of shame and sorrow for all of us. Let's resolve that we will not let her death go in vain.
"Aren't we all responsible for her death? Can we all now do something so that half of humanity starts feeling safe amongst us?" he said.
The mourners protested against the security lock down of India Gate and Raisina Hill where violent demonstrations were witnessed last weekend over the rape.
"The government is not even allowing mourning of the death. This is insensitivity. There is complete lock down. You have the metro stations shut. You have a road completely blocked. This is undemocratic," a protester Sunil said.
Sisodia said the government was muzzling the voice of people by shutting Metro and closing down India Gate.
In a statement, AAP said the girl, who became the symbol of women