A 50-year-old inmate of Dhaka Central Jail in Keraniganj died at Dhaka Medical College and Hospital (DMCH) early Wednesday.
The deceased was identified as Syed Alam.
Inspector Bachchu Mia, in charge of Dhaka Medical College and Hospital police camp, said Alam was brought to the hospital around 1:30 am as he fell sick at the Dhaka Central Jail in Keraniganj.
Later, the on-duty doctors declared him dead, he said.
The body was kept at the hospital morgue for an autopsy.