- Ruby Rai, 17, arrested on Saturday in Bihar for cheating
- Unfair to arrest school girl in cheating conspiracy, say critics
- Toppers in Bihar exams could not answer basic questions
Education Minister Upendra Kushwaha says in particular, Ms Rai's father, Avadesh Rai, was complicit in the conspiracy forged by Bacha Rai, the owner of a privately run college, who is among the 20 people arrested so far in the scandal.
Ms Rai, after being declared the topper in Political Science, told reporters on camera that the subject included cooking.
With several other toppers failing basic questions, all of them from the same institution, the police appointed a special team to identify the show-runners of the cheating conspiracy, which allegedly include government education officials.
Teachers and state education officials were left red-faced last year after television footage showed scores of desperate parents and others scaling outer walls of buildings to pass books and pieces of paper to students inside taking exams.
Ms Rai was arrested after she attempted to take a special re-test and interview ordered by the Bihar School Examination Board - and failed to correctly answer a single question.
The police says that while being interrogated, she revealed that her father had promised her he would "take care of the results" and that investigators are now trying to establish that he bribed officials to land the top spot for her.
"I wanted a second division, I never thought I would be a topper," Ms Rai reportedly told investigators.