Since 1983, the former West German Army officer had led various outlawed groups.
Members of an outlawed Islamist group confessed to the attack last month.
Such conditions have provided fertile recruiting ground for the African National Congress, the principal outlawed group seeking to overthrow apartheid.
The outlawed group appears to have stepped up the hijacking campaign in recent days after periodic transmissions began during the summer.
Two members of an outlawed group promoting reunification of the two countries were arrested today on their way to the border with North Korea.
Also today, English-language newspapers around the country attacked new restrictions on reporting about outlawed black groups.
Police initially said the crime was committed by an outlawed Muslim militant group.
The convictions included illegal possession of weapons, attempting to overthrow the Government and leading outlawed groups.
All three had been convicted of membership in an outlawed leftist group.
Prekaz, a village of about 1,000, was well known as a stronghold of the outlawed group.