As many as 59 prisoners in Thiruvananthapuram jail tested positive for coronavirus on Wednesday, officials said.
This came after antigen tests were conducted on 99 prisoners following a 71-year-old prisoner testing positive on Tuesday.
Of the 99 tests done, 59 came out positive.
With a large number testing positive for COVID-19, jail authorities have decided to test all the remaining inmates also.
The prison houses 975 inmates, including both women and men.
A decision has also been taken that all those who have tested positive will now be moved to the makeshift COVID treatment centre in the jail auditorium.