NEW DELHI (REUTERS) - Students and staff at an elite Indian university on Thursday (March 19) demanded the reinstatement of a prominent academic, who they say was forced to resign in an attack on freedom of speech.

Professor Pratap Bhanu Mehta, one of India's best-known intellectuals and a vocal government critic, resigned from the private Ashoka University, north of the capital New Delhi, on Tuesday.

His decision led to the resignation of a second prominent academic on Thursday and protests at Ashoka, founded in 2014 as an Indian alternative to the US Ivy League colleges.

"We strongly condemn the conditions that led to these resignations and the lack of transparency from the university," a statement by the university's student body said, demanding that Prof Mehta be re-offered his position.

Prof Mehta - a former vice-chancellor and hugely popular figure at the university - did not respond to a request for comment, and the reasons for his resignation have not been made public.

A group of students protested against Prof Mehta's resignation on the campus on Thursday, according to e-mails and social media posts.

The second academic to resign, Professor Arvind Subramanian, a former chief economic adviser of Prime Minister Narendra Modi's government, said the news regarding Prof Mehta was "troubling".

"The circumstances involving the 'resignation' of Professor Pratap Bhanu Mehta, who is not just a dear friend but a truly inspirational national figure, have devastated me," Prof Subramanian said, according to copy of his resignation letter shared between fellow academics and first reported by the Indian Express.

"That even Ashoka - with its private status and backing by private capital - can no longer provide a space for academic expression and freedom is ominously disturbing."

Prof Subramanian could not be reached for further comment.

Current vice-chancellor Malabika Sarkar did not respond to a request for comment.

Critics have accused the Modi government of trying to suppress dissent. Earlier this month, a US-based think-tank downgraded India's democracy from free to "partly free", drawing fury from New Delhi.

The government rejects the allegation and said it did not need approval from foreign organisations.