A senior leader of India's main opposition Bharatiya Janata Party (BJP) has been shot in Mumbai (Bombay), according to police.
Mr Mahajan is an influential political voice in India
Pramod Mahajan, a BJP general secretary and a former federal minister, was allegedly shot by his brother after an altercation in a family dispute.
Doctors said the condition of Mr Mahajan, 56, was "quite critical" following surgery lasting four hours.
Indian TV channels report his brother, Praveen, has surrendered to police.
Praveen's lawyer, Nandkumar Rajukar, told NDTV television his client had been suffering from "some mental disorder".
He is "completely under depression, under mental trauma. He is not in a position to speak properly or tell exactly what exactly happened," Mr Rajukar said on television, reports the Associated Press.
Suggestions that Praveen, 45, who is a building contractor, quarrelled with his brother over a property deal have been dismissed by police and Mr Mahajan's family.
Mr Mahajan was admitted to Hinduja Hospital with injuries to his chest and stomach.
Dr Varma told reporters that the surgery had been carried out to stop the bleeding from the affected organs and that the three bullets were still lodged inside the body.
"The bullets have damaged his liver, pancreas and small intestine resulting in massive blood loss. He is on ventilatory support and his condition is quite critical," he said.
Mr Mahajan belongs to the BJP's Generation Next - a group of relatively younger "technocrat" leaders who lack a grassroots political base.
Mumbai Joint Commissioner of Police Aroop Patnaik said the incident happened between 0730 and 0800 (0200-0230GMT).
Three shots were allegedly fired by Praveen Mahajan from his licensed revolver.
Mr Mahajan's security did not prevent Praveen entering the BJP leader's 15th floor flat in Mumbai because he was his brother, added Commissioner Patnaik.
He said it was "a private and domestic affair".
"We are shocked by the news. We are praying for his speedy recovery," BJP leader Venkaiah Naidu told NDTV news channel.