India's 'cockroach' protesters are back - this time asking poll chief to resign

India's influential Gen Z-led "cockroach" protesters are back on the streets - this time seeking electoral reforms and the resignation of Chief Election Commissioner (CEC) Gyanesh Kumar over allegations of manipulating voter rolls.

A pressure group which began as an online satirical movement, the Cockroach Janta Party (CJP) recorded its first major victory in July when it forced education minister Dharmendra Pradhan to resign after weeks of protests calling for education reforms.

CEC Kumar or the Election Commission have not responded to the calls for his resignation from the CJP or opposition parties. They have also not responded to allegations of vote theft or elections being rigged. The BBC has asked them for comment.

On Friday, thousands of people joined a protest called by the CJP at the sprawling Shivaji Park grounds in Mumbai city "to save democracy" and seek CEC Kumar's resignation.

The CJP has said this is the first in a series of demonstrations it plans to hold across the country in October, culminating in a rally in the capital, Delhi.

Most people in the crowds were young supporters of the CJP - some told the BBC they had come from the far suburbs of Mumbai and even from outside the city, from places such as Nagpur.

There was a heavy police presence at the venue. A small stage was set up on a truck from where CJP leaders are speaking.

In Delhi, however, police detained hundreds of people who were trying to protest at Jantar Mantar, a central site in the capital where the last CJP protest took place.

The CJP called the protest after last week's report in The Indian Express that CEC Kumar's two fellow election commissioners, Sukhbir Singh Sandhu and Vivek Joshi, had formally objected at least 14 times over 10 months to decisions and orders they said had been issued without their knowledge.

The differences were reported to be mostly over a controversial revision of the country's electoral rolls known as the Special Intensive Revision, or SIR, which began last year.

The Election Commission says the exercise is intended to remove duplicate and ineligible entries - and so far, 130 million names have been struck off the voters' list.

But opposition parties and activists have alleged that many of those are eligible voters and that the process is being manipulated by CEC Kumar to favour Prime Minister Narendra Modi's Bharatiya Janata Party (BJP) during elections. Both the BJP and the Election Commission have rejected the accusations.

Last week's Indian Express report said the two commissioners had also been raising questions over the integrity of the voter database, changes to the way new voters are enrolled and the security of the electoral rolls itself.

The EC defended its way of working and said in a statement that "differing views" were part of the "decision-making process" and that all the decisions were taken unanimously.

But the revelations sparked a furore, with opposition leaders demanding Kumar's resignation.

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Leader of the opposition and senior Congress party leader Rahul Gandhi has repeatedly accused the commission of "stealing votes from the opposition" and said those officers who were indulging in "vote theft" were "traitors".

Another senior opposition leader, Mamata Banerjee, has demanded the CEC's arrest.

On Wednesday, the INDIA alliance - an opposition grouping that includes nearly two dozen parties and has both Gandhi and Banerjee as members - said they would also organise protest rallies across the country in the coming days. On 6 October, all opposition MPs plan to march to the Election Commission office in Delhi, they added.