CAIRO, Aug 13 (Aswat Masriya) - An Egyptian misdemeanour court reduced a prison sentence of a policeman convicted of manslaughter in the Abu Zaabal police van case from 10 years to five years during a retrial on Thursday.

The court also upheld the suspended prison sentences three police officers were handed last year.

Thursday's sentences can all be appealed at the cassation court.

The case was brought to court after the deaths of 37 detainees inside a police van in August 2013. The incident took place outside the Abu Zaabal prison.

The 37 deceased detainees were arrested following the forcible dispersal of the pro-Mohamed Mursi Rabaa al-Adawiya sit-in on August 14, 2013. Their deaths are alleged to have been caused by policemen firing a teargas canister inside the van. 

Investigations revealed that the ventilation system in the police van was broken and that there were 45 prisoners inside the car, while its capacity could accommodate no more than 24 persons.

The prosecutor-general leveled the four policemen with manslaughter charges, citing the inability to prove their criminal intent in murder, a prerequisite in pressing first-degree-murder charges.

A misdemeanour court sentenced the vice warden of the Heliopolis police station to 10 years in prison in March 2014, while three police officers were served a suspended sentence of one year in prison each.

In June, 2014 a misdemeanour court of appeals cancelled sentences handed to the police officers and returned the case to prosecution for more investigation. Overturning the verdict paved the way for the retrial.