Protesters, some in paper cockroach masks -- a reference to reported remarks by India's top judge -- called for the resignation of Education Minister Dharmendra Pradhan over the irregularities, including question paper leaks and technical glitches.

"We want accountability from the government," 16-year-old Utkarsh Raj, who hopes to pursue a medical career, told AFP.

"How is it that exam papers get leaked in this country? How is this right?"

The protest, watched closely by police officers in riot gear, was led by Abhijeet Dipke, whose parody "Cockroach Janta Party" (CJP) -- a play on Prime Minister Narendra Modi's Hindu-nationalist Bharatiya Janata Party (BJP) -- has won millions of followers on social media since its launch last month.

"This protest is for the future of this country. This protest is for jobs," Dipke, a former political communications strategist for the opposition Aam Aadmi Party, told the rally.

"The youth of the country... will fight," said the 30-year-old organiser, who returned to India from the United States on Saturday.

The movement emerged after India's Chief Justice Surya Kant reportedly likened young people who criticised the government to "cockroaches" and "parasites" during a court hearing, sparking outrage.

Kant later said his comments were taken out of context.

Despite rapid economic growth, millions of people in the world's most populous nation still struggle to find stable and well-paying jobs, fuelling discontent.

- 'No credibility' -

Last month, authorities scrapped the nationwide medical college entrance test, one of the country's most competitive exams, after investigators uncovered a question paper leak.

That came on top of another scandal related to the online marking system of tests taken by nearly two million high school students.

"India deserves better administration of such crucial exams," said 20-year-old protester Sarthak, who gave only one name.

Sapan Gyan, 52, who accompanied his sons to the protest, said that "young people... can't have a situation where these exam systems have no credibility left."

Environmental activist Sonam Wangchuk, 59, who has been at loggerheads with the government over demands for greater autonomy for the Himalayan region of Ladakh, said the students affected by the exam failures "have no voice, no say".

The CJP -- whose pages have been blocked on some social media platforms -- has over 22 million followers on Instagram, well above Modi's ruling party or India's main opposition party.

In recent years, some of India's neighbours including Bangladesh and Nepal have witnessed youth-led movements against perceived corruption and political apathy that toppled incumbent governments.