The convicts were also sentenced to additional 36 months imprisonment in hard labor each for attempting to escape from lawful custody.
The sentences are to run concurrently.
They are Mohammed Issa, Raphael Lawoe, Mohammadu Gariba and Okorley Ebenezer Tetteh.
Gariba Amadu, the fifth accused person, was sentenced to 36 month imprisonment in hard labor for attempting to escape from lawful custody.
All accused persons pleaded not guilty to their charges.
Amadu, a Beninoi, is serving a previous 50 year sentence for armed robbery while Mohammed Gariba, a Nigerian, was jailed 60 years for the same offence.
Mohammed Issa, a Malian, is also serving a 50 year sentence for armed robbery, while Raphael Lawoe and Okorley Ebenezer Tetteh, who are Ghanaians, were previously jailed 40 years each for armed robbery.