His condition is "very critical", doctors attending on him said on Saturday.
Pravin, 50, who was out on a 14-day parole, was admitted to the Jupiter Hospital last night after he complained of fatigue and severe headache at home, family sources said.
"Pravin has suffered an extensive pontine haemorrhage (brain haemorrhage) and is currently on a life support system.
His condition is very critical and he is deeply unconscious," a health bulletin released by the hospital here said.
Pravin was found guilty of shooting his brother in Mumbai on April 22, 2006. Pramod succumbed to bullet injuries 12 days later.
He was awarded life imprisonment by a Mumbai court in December 2007 and lodged at the Nashik Central Jail.
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