An Indian court awarded a life sentence on Monday to a police volunteer convicted of the rape and murder of a junior doctor at the hospital where she worked in the eastern city of Kolkata, rejecting demands for the death penalty and saying it was not a rare crime.

The decision to challenge the trial court’s sentence of life imprisonment came hours after the central agency opposed a similar plea by the state government.

An Indian court on Monday sentenced a police volunteer to life imprisonment for the rape and murder of an on-duty doctor last year – a crime that sparked nationwide protests. Sanjay Roy, 33, plans to appeal the judgment in a higher court.

The CBI is likely to file the appeal against the Sealdah court order by Friday with detailed arguments in favour of capital punishment, they said.

The police had sought the death penalty in a horrific but familiar crime. Its handling by the local authorities had outraged the nation.