Authorities shut down roads in the heart of India's capital on Monday to put an end to a week of demonstrations against the brutal gang-rape of a woman on a moving bus.

Thousands of armed police and paramilitary troops blocked roads in central New Delhi to prevent protesters from marching to the presidential palace. A small group of demonstrators gathered at a venue about a kilometre away from India's parliament to press the government to ensure the security of women in the city.

The city ground to a halt as commuters found themselves caught in massive traffic jams after most roads in central Delhi were barricaded by police.

Prime Minister Manmohan Singh appealed for calm and promised that the government would take tough action to prevent crimes against women. There has been outrage across India over the Dec. 16 rape that left the young woman in critical condition in a hospital.

There has been outrage across India over the Dec. 16 gang rape that left the young woman in critical condition in a hospital. (Adnan Abidi/Reuters)

"Anger at this crime is justified, but violence will serve no purpose," Singh told protesters.

He assured them that the government would "make all possible efforts to ensure security and safety of women in this country."

Police have used tear gas and water cannons and hit protesters with batons during the protests, leading to widespread criticism of authorities for the use of excessive force.

The demonstrations have continued despite repeated promises by Home Minister Sushilkumar Shinde that he will consider protesters' demands that all six suspects who have been arrested following the attack face the death penalty.