A German court convicted a former top spy in Yugoslavia's secret service and his one-time subordinate of involvement in the 1983 killing of a Communist-era dissident, and sentenced them on Wednesday to life in prison.

Zdravko Mustac and former subordinate Josip Perkovic, who later created independent Croatia's spy agency, went on trial in Munich in October 2014 — months after they were extradited from Croatia.

The Munich state court said judges convicted the two men of complicity in the murder of Stjepan Djurekovic. The dissident was shot and beaten on July 28, 1983, in a garage in Wolfratshausen, near Munich.

The court found that Mustac, the SDS agency's political head at the time, ordered Perkovic in late 1982 or early 1983 to plan and prepare the killing.

It said that Perkovic obtained a key to the building where the killing occurred with the help of a third man, who was convicted in a separate trial. He then passed on the key to the three or four people who carried out the killing, the court found.

The killers have never been identified.

The defense had sought the two men's acquittal, arguing that there was a lack of evidence.