The convicts, Gambo Musa, Mana Musa, Abdu Baba and Mohammed Muazu (who died in custody), were found guilty of abduction and armed robbery.
The convicts were said to have robbed and abducted the Adamawa House of Assembly member representing Toungo constituency, Adamu Usman, and a retired civil servant, Wilson Gundiri.
Delivering judgement, the judge, Abdul-Azeez Waziri, gave the convicts 10 years each for conspiracy to commit abduction and death sentence for armed robbery.
Earlier, Waziri had on Monday sentenced five men to death for killing a herdsman.
The convicts, Alex Amos, Alheri Phanuel, Holy Boniface, Jerry Gideon and Jari Sabagi of Demsa Local Government Area of Adamawa were found guilty of criminal conspiracy and culpable homicide.
They killed a herdsman and dumped his body into a river in Kadomon village after hacking several of his cattle.