Indian "cockroach" movement founder Abhijeet Dipke has been reportedly arrested by police ahead of a rally in New Delhi.
Dipke was arrested to prevent a breach of the peace and will be called before a court, broadcasters NDTV and India Today said. The broadcasters did not give a court date.
The youth-led Cockroach Janta Party (CJP), opposition groups and student organisations have held near-daily protests this month demanding Chief Election Commissioner Gyanesh Kumar's resignation over a revision of voter lists that they say favours Prime Minister Narendra Modi's Bharatiya Janata Party (BJP).
More than 130 million voters were deleted during the revision. The Election Commission has denied favouring any party and said wrongly deleted voters can re-enrol. The BJP has accused rivals of trying to undermine democracy by wrongly questioning legitimate electoral processes.
Dipke was detained on Friday as he stepped out of a house in central Delhi, with police hauling him into a police car and driving away after a brief argument.
Dipke had called Friday's protest in support of two CJP leaders detained and sent to jail this week for five days for demonstrating at a protest site in violation of a ban.
Earlier, police had met Dipke and warned him against going ahead with the protest.
Student activist Neha Bora, a prominent face of the protests, was also detained on Friday as she tried to reach central Delhi with dozens of supporters but was later released.
"I have been released!" she said on X.