"Replacing the jammers with the upgraded version is needed because the present jammers cannot prevent use of hi-tech 3G and 4G phones. We have already installed upgraded versions of jammer in some jails," Inspector General (Prison), Pradip Kapoor said.
The jammers will be installed in eight major jails and at least a dozen more prisons in Odisha, he said.
The inspector general (Prison) was here to attend the passing out ceremony of assistant and sub-assistant jailors in Odisha jail training school.
He said at least six more sub-jails would be opened this year. The sub-jails with the combined capacity of 450, would be opened at Soro (Balasore, Patrapur (Ganjam), Laxmipur (Koraput) MV-79 (Malkangiri), Kantabanji (Balangir) and Kasipur (Rayagada).
"Construction work of the new sub-jails is almost complete," he said.