Mr Goyal cited reports that Rohith's mother Radhika Vemula had accused the Kerala-based Indian Union Muslim League, or IUML, of not giving her the promised Rs 20 lakh to attend political rallies where false allegations against the BJP were allegedly levelled. Rahul Gandhi had also shared stage with her, the minister said, claiming that it should be found out what allurements were offered to her.
"Rahul Gandhi must apologise to the nation... He along with others has made a tool of this distressed mother... I feel terribly sorry for the family...," Mr Goyal said at an unusual press conference.
Ms Vemula has been a sharp and consistent critic of the BJP-led government ever since son Rohith committed suicide inside the Hyderabad university campus in January 2016. The suicide had triggered a massive row after the research scholar's friends alleged that the university administration had targeted him on complaints backed by BJP ministers.
Radhika Vemula accused the BJP of indulging in slander and lies, saying that she did not need money to attack the BJP.
"I will criticise the BJP and Narendra Modi on any forum because I hold them responsible for my son's death," Ms Vemula told NDTV minutes after senior BJP leader Piyush Goyal's unusual press conference.
Radhika Vemula said she did tell an online media outlet that the IUML had promised her money to buy a house soon after Rohit's death.
She had got two cheques of 2.5 lakh rupees each last month but one of them could not be encashed. She had expressed disappointment but insists the money was not quid pro quo for criticising Modi.
The IUML contends that the cheque was returned only because of a spelling error.
Congress's chief spokesperson Randeep Surjewala said it was Prime Minister Narendra Modi and Piyush Goyal should apologise to Rohith Vemula's mother for attempting to tarnish his memory.
"This is a classic BJP style of peddling fake news... they first promote it through some website, then its picked up by some bhakt news channel... and then to perpetuate these lies via press conferences by ministers. This is a systematic pattern of the dirty tricks department of the BJP," he said.
Ms Vemula also rebutted oblique insinuation that she took money to make an appearance or speech at any public meeting.
She said organisers did make her travel arrangements and stay but did not pay her for criticising PM Modi and the BJP.
"I still earn my livelihood stitching clothes," Radhika Vemula said. "The couple of times I was paid 5000 to 10,000 rupees, I used that money to support the schooling of six poor students in Guntur," she said.
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