YOGYAKARTA, Indonesia — An Indonesian military court sentenced eight soldiers from an army special forces unit to up to 11 years in jail Thursday for their involvement in the execution of four prisoners to avenge the murder of a fellow soldier.
Twelve well-trained troops wore masks as they broke into Cebongan prison in Yogyakarta province, on the main island of Java, on March 23, seeking out four men being held on charges of killing another member of their special unit, known as Kopassus.
After torturing and forcing several guards to open the jail cell, they shot the inmates with automatic weapons and destroyed surveillance cameras.
The case sparked a national outcry among Indonesians demanding that the military not be allowed to operate with impunity. In a rare acknowledgment of military abuses, the government issued a statement after the attack, promising justice would be served.
However, police said the four inmates who were killed were gang members, and some local residents believed the soldiers were deterring other thugs who have created disturbances in Yogyakarta, an ancient province and a tourist destination. They staged rallies during the trials, calling on the court to free the defendants.
The 12 soldiers were tried in four groups at the military court in Yogyakarta.
The presiding judge, Lieutenant Colonel Joko Sasmito, told the court Thursday that Second Sergeant Ucok Tigor Simbolon, 36, had been found guilty of executing all four detainees and sentenced to 11 years in prison.
Two other soldiers were sentenced to eight and six years for helping with the executions.
‘‘Their actions have damaged the image of the Indonesian military,’’ Sasmito said.