NEW DELHI — India’s opposition parties marched toward the Supreme Court on Monday to protest a purge of voter lists they say favors Prime Minister Narendra Modi’s party, after police detained thousands of activists over the weekend in a sweeping crackdown.

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

Protests led by the “Cockroach” youth movement have intensified since election authorities began the revision last year, removing more than 130 million voters from the lists. Critics say the process is politically motivated and risks disenfranchising eligible voters. Modi’s Bharatiya Janata Party and the Election Commission deny allegations of manipulation, saying the move is needed to remove duplicate and ineligible names.

Ahead of the march, authorities closed six metro stations in the capital on Monday and warned of traffic disruptions.

Opposition leader Rahul Gandhi of the Congress party described the growing protests as a fight to defend the constitution.

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

Police detained thousands of demonstrators in New Delhi over the weekend, including leaders of the “Cockroach” movement. Earlier protests led by the group forced the resignation of Modi’s education minister in July.

Modi has not publicly commented on the protests, but leaders of his party have dismissed them, with some calling the activists “anarchists.”