The measure is being taken as Covid-19 infected inmates are being directed to the Welikada Prison.
It is said that they are being kept in a area which usually houses prison officials and government officials.
Primalal Jayasekara has been sentenced to death for shooting dead a man during an campaign rally in Kahawatta ahead of the 2015 presidential election.
Duminda Silva has been imprisoned for nearly 05 years after being sentenced to death over the murder of former MP Bharatha Lakshman Premachandra.
Sampath Vidanapathirana is being imprisoned for the murder of the British national - Khurram Shaikh and the rape of his Russian girlfriend.
Not transferred to Mahara?
Although it was earlier planned to transfer the three of them to Mahara prison, the decision was changed after the riot and the spread of Covid-19 among Mahara inmates.
Meanwhile, after conducting a rapid antigen test on 2600 inmates at the Welikada Prison yesterday (12), it has been confirmed that 95 of them have tested positive for Covid-19.
Prison sources say that about 60 infected prisoners, including 22 inmates in the death row and former DIG Vass Gunawardena, have been directed to the Welikada Prison Hospital.
Other prisoners, including those on death row, have been admitted to Gallella Hospital.
However, it is reported that the son of DIG Vass Gunawardena, who is being held in the same cell, has not been infected.