Opposition parties in India marched toward the Supreme Court on Monday to protest a voter list revision they allege benefits Prime Minister Narendra Modi’s party, following a major police crackdown that saw thousands of activists detained over the weekend.

Opposition lawmakers and supporters sought to submit a petition to the chief justice, calling for the resignation of Chief Election Commissioner Gyanesh Kumar.

The protests, spearheaded by the youth movement known as “Cockroach,” have gained momentum since election authorities launched the voter list revision last year. More than 130 million names have reportedly been removed from the electoral rolls.

Critics argue that the exercise is politically motivated and could deprive eligible citizens of their voting rights. However, Modi’s Bharatiya Janata Party (BJP) and the Election Commission have rejected allegations of manipulation, saying the revision aims to eliminate duplicate and ineligible entries.

Ahead of Monday’s demonstration, authorities shut down six metro stations in the capital and issued warnings of possible traffic disruptions.

Congress leader Rahul Gandhi described the growing protests as a struggle to protect India’s Constitution.

“We will not back down,” he told reporters in New Delhi.

Police detained thousands of protesters in the capital over the weekend, including leaders of the “Cockroach” movement.

The group had previously led demonstrations that culminated in the resignation of Modi’s education minister in July.

Modi has not publicly commented on the latest protests. However, leaders of his party have dismissed the demonstrations, with some describing the activists as “anarchists.”