The incident took place around 2 a.m when undertrial Sopan Pagre, 25, charged in a murder case, attacked his cell mates.
Pagre reportedly tore down a wooden board from the toilet door and pounded the heads of the two other inmates, Vishal Choudhary, 21 and 22-year-old Vijay Ipper.
Despite the screams of the two youths, Pagre continued hitting his victims until he was overpowered by several other inmates and jail guards.
The motive behind the attack is not clear. Pagre was slapped with additional charges of murder and attempt to murder.
The heavily bleeding inmates were rushed to the prison hospital where Choudhary died in the morning and Ipper is in a critical condition.
According to preliminary investigations, Pagre and the victims quarrelled over a petty matter after which the two heckled him.
The prison authorities have ordered a probe into the incident.
Nashik Central Jail has around 2,300 prisoners and 250 staffers and is counted among the high security prisons in Maharashtra.
In other recent cases of violence in Maharashtra's prisons, a suspect in Pune's German Bakery blast and Bangalore Chinnaswamy Stadium blast cases, Mohammed Jaffer Siddiqui was killed by some inmates inside the high security Anda Cell at Yerawada Central Jail in Pune last year.
Earlier this year, gangster Abu Salem was shot at in the Taloja Central Jail by an undertrial Devendra Jagtap, accused of killing Mumbai lawyer Shahid Azmi.
--IANS (Posted on 16-10-2013)