Lawyer Santosh Kumar Suman (32), a member of the Supreme Court Bar Association, stood on the desk, took off his shirt and shouted, "Prime Minister, go back. Roll back diesel prices."
The incident took place at Vigyan Bhawan where Singh walked to the rostrum to deliver his address 'Conference on Economic Growth in Asia and Changes of Corporate Environment'.
The Prime Minister waited for a while at the rostrum as security officials took the lone protestor out of the plenary hall of Vigyan Bhawan.
Security personnels immediately whisked the lawyer out of the venue.
A senior police official said Suman, who resides in east Delhi's Shakarpur, gained entry to the venue using a "proper" invitation card.
"The Special Protection Group (SPG) handed him over to us. He is under detention. We are investigating claims that he is a member of political party RJD," the official said.
The conference, organised by Indian Law Institute, was attended by legal luminaries from across Asia besides Chief Justice of India S H Kapadia and Law Minister Salman Khurshid.
