"Special constitutional arrangements were made to effectively check the terrorists and terrorism," ISPR said in a statement.
"Routine judicial system was under stress wherein judicial set-ups and judges were also subjected to acts of terrorism," the statement read while justifying the establishment of the said courts.
"During the period of its validity, 274 cases were referred to Military Courts. Of these 161 were awarded death penalty (12 executed) and 113 were awarded imprisonment of varying duration," it said.
"The disposal through military courts has yielded positive effects towards reduction in terrorists' activities," it added.
Pakistan had legalised military court trials of terror suspects for a period of two years in January 2015, soon after terrorists killed 144 people, mostly children, at Army Public School (APS) in Peshawar.