NEW DELHI: Students involved in a massive weekend protest at a predominantly Muslim university in India's capital described a clash with baton-wielding police at a news conference Tuesday, as opposition grew nationwide against a new law that provides a path to citizenship for non-Muslim migrants.

A peaceful march by students from New Delhi's Jamia Millia Islamia University descended into chaos Sunday when demonstrators set three buses on fire. Police responded with rubber bullets and tear gas. Video footage showed officers running after fleeing protesters and beating them with wooden sticks.

“The 15th of December is a black day in the history of this country," human rights activist Farah Naqvi said at the news conference.

The police response to Sunday's protest has drawn widespread condemnation and seems to have sparked an even broader movement against the Citizenship Amendment Act. The new law applies to Hindus, Christians and other religious minorities who are in India illegally but can demonstrate religious persecution in Muslim-majority Bangladesh, Pakistan and Afghanistan.

It does not apply to Muslims.

Prime Minister Narendra Modi's ruling Hindu nationalist Bharatiya Janata Party has painted the new law as a humanitarian gesture, but critics say it is intended to help the party transform a multicultural and secular India into a Hindu “rastra," or distinctly Hindu state.