More than 100,000 people have joined a demonstration in southern India to protest a controversial citizenship law that critics say discriminates against the minority Muslim community and undermines the country’s secular constitution.

The demonstration - dubbed ‘Million March’ - was organized by an umbrella group of Muslim and civil society organizations in the southeastern city of Hyderabad on Saturday to protest India’s new Citizenship Amendment Act (CAA).

Protesters chanted We want justice, and held signs that read Protest against CAA.

More than 40 percent of Hyderabad’s estimated population of nearly seven million is Muslim.

Protests against the contentious law also went ahead in several other Indian cities on Saturday, with hundreds turning out in cities in the southern state of Karnataka.

The demonstrators accused the government of Indian Prime Minister Narendra Modi of trying to divide the country along communal lines, to distract from a sharp domestic economic slowdown and job losses.

India has been rocked by the protests since December 11, when Modi’s ruling Hindu nationalist Bharatiya Janata Party (BJP) passed the law, easing the way for non-Muslim migrants from the neighboring Muslim-majority nations of Afghanistan, Bangladesh, and Pakistan to gain Indian citizenship.

Some demonstrations have turned violent, particularly in the populous northern state of Uttar Pradesh, and at least 26 people have been killed in clashes with police since early December.

Heavy-handed police tactics have fueled anger, with many accusing authorities of arbitrary force against the protesters.

The demonstrations across India are the biggest challenge to the prime minister since he first came to power in 2014.