The suicide of a Dalit research scholar at a Hyderabad Central University hostel prompted an FIR today that slaps abetment charges on Union labour minister Bandaru Dattatreya and vice-chancellor Appa Rao.

Officers said student complaints had led to the FIR that accuses five persons of abetting Rohith Vemula's suicide, punishable by up to 10 years in jail, and also charges them under the SC and ST (Prevention of Atrocities) Act.

Dattatreya is accused of having written to human resource development minister Smriti Irani in August complaining against the "anti-national politics" of Dalit student body Ambedkar Students Association (ASA), to which Rohith belonged.

Student protesters alleged the letter had played a part in the university expelling five ASA members, all research scholars, from their hostels on the charge of attacking members of Rashtriya Swayamsevak Sangh student wing ABVP. They were evicted on January 4.

Rohith, 28, who was one of the five, stepped into an empty hostel room yesterday morning and hanged himself, leaving behind a note that said: "No one has instigated me, whether by their acts or by their words, to this act."

Dattatreya, BJP parliamentarian from Secunderabad, denied any role in the happenings at the university and said he had merely forwarded an ABVP representation to Irani along with a covering letter.

"Anti-social, anti-national activities were going on in the university. ABVP activists were beaten up," PTI quoted him as saying in Delhi. "I don't know what action they (the university) did (take). The BJP or I have nothing to do with the incident."

Police sources said the three other accused are MLC Ramachandra Rao of the BJP, ABVP leader Susheel Kumar and his brother and fellow student Vishnu.

As news of the suicide spread, about 500 students gathered before Irani's office in Delhi and chanted slogans against her, prompting police to beat them back with water cannons. The Congress demanded the sack for Dattatreya.

In Hyderabad, about 800 students marched in the afternoon demanding immediate arrest of the minister and the vice-chancellor.

The students said the seeds of the suicide were sown in August last year when the ABVP disrupted a campus screening of Muzaffarnagar Baaqi Hai, a documentary on the September 2013 communal violence.

When the ASA issued a joint condemnation with Dalit student bodies from across India, the ABVP allegedly made derogatory remarks against the organisation on Facebook. This apparently led to a confrontation between the five Dalit scholars and Susheel.

A scanned copy of Dattatreya's letter, given to The Telegraph by student sources, accuses the ASA of protesting 1993 blast convict Yakub Memon's hanging and beating up "Shushil Kumar, President, ABVP" when he objected.

The letter describes the university as a "den of casteist, extremist and anti-national politics" and asks Irani to change the campus "for the better".

In Delhi, sources in Irani's ministry said she had forwarded the letter to the university asking it "to look into it".

Irani today sent a fact-finding team of two senior officials who have to submit a report "as early as possible".

Since their eviction, the five scholars had been holding a "sleep-in protest", spending their nights under a makeshift "tent" on the campus lawns. They had also moved high court saying they could not afford rooms outside the campus.

Appa Rao expressed shock at Rohith's suicide and said the university had not stopped the five from "utilising any facilities" apart from their hostels. "I have not acted on any direction from Delhi," he said.

Students said the five were denied access to all campus buildings and facilities except their classrooms, the library and conferences and workshops related to their subjects.

Student groups have resolved to continue their protest on the campus, where Section 144 has been imposed and police pickets put up.

The police have asked Rohith's family to cremate him in hometown Guntur. All those visiting the Osmania General Hospital's morgue, where the post-mortem was done, were taken into preventive custody.

Rohit, son of a security guard and a day labourer, was doing his PhD on "science, technology and society".

"I always wanted to be a writer. A writer of science, like Carl Sagan. At last, this is the only letter I am getting to write," his suicide note said.

Arpita Jaya, a student leader from Rohit's university, said 10 Dalit students had committed suicide in the past 10 years at the institution, where they were often taunted and discriminated against.

The students plan to protest indefinitely and are in touch with their peers in other universities.

The BJP issued a statement expressing sadness at the suicide but stressed that the ASA group had attacked Susheel.

It said the university's executive council had decided to expel the five but the ASA "did not allow the university administration to function for two days", forcing then vice-chancellor R.P. Sharma "to withdraw the order with a condition that the matter will be looked into afresh".

A sub-committee was set up for a fresh inquiry after Dattatreya's letter to Irani, sources said. By the time its recommendation for action came, Appa Rao had taken over.