Most of the 58 inmates were initially incarcerated at Pasir Putih and Batu prisons, the two most secure facilities on Nusakambangan prison island, Antara News Agency reported.

The police and the military deployed hundreds of personnel to secure the relocation process to Gunung Sindur, which also has special maximum-security blocks for high-risk inmates, just like on Nusakambangan.

Yet it remains unclear if the 58 detainees are high-risk inmates or if they are among the 145 inmates involved in a deadly riot in a detention center at the National Police’s Mobile Brigade headquarters (Mako Brimob) two weeks ago, as authorities were tight-lipped on the details.

Ade Kusmanto of the Correctional Facilities Directorate General at the Law and Human Rights Ministry revealed only their status of custody.

“All of the inmates are detainees who are standing trial,” he said on Sunday as quoted by Antara.

When the standoff at the Mako Brimob detention center in Depok, West Java, came to an end on May 10, authorities were quick to send 145 terror inmates allegedly involved in the deadly incident to Nusakambangan.

The government has also pledged to review prisoner placement and handling procedures, as well as gradually separating all terror detainees from detainees of other crimes across the country and impose a one-man, one-prison-cell system for high-risk terror inmates.