The trial has begun in Iraq of 36 men accused of involvement in one of the worst atrocities carried out by the Islamic State of Iraq and the Levant (ISIL) group.

Human rights groups have accused the Iraqi government of cutting corners in the run-up to Sunday's hearings, but families of the 1,500 soldiers who were captured and killed are demanding justice.

ISIL killed the men after taking them prisoner at Camp Speicher, a former US base outside the city of Tikrit, during its June 2014 offensive in western Iraq.

ISIL suspects stand trial over Camp Speicher massacre

Their remains were buried in mass graves and only discovered after Iraqi government forces recaptured the area in April this year.

The group posted pictures of the men being led away by its fighters and shot dead in ditches shortly after the massacre.

Of the 1,500 victims, only 400 have been found and many of those killed are still missing and families are still waiting to bury their loved ones.

Al Jazeera spoke to Tamkeen al-Moussawi, whose son Karar was killed during the massacre.

"The government keeps saying it will capture those who killed our sons. But I still have not received the remains of my dead son and the perpetrators have not been brought to justice," Moussawi said.

"We want justice to be served quickly."

Of the 600 people wanted by Iraqi authorities in connection with the massacre, only 24 people have been convicted so far.

In July, a group of 28 men went on trial in Baghdad over the Camp Speicher killings, all but four of the men were given death sentences, with the remainder acquitted for lack of evidence.

The sentencing was greeted by cheers from the families of victims present, with many shouting "God is Great" and "Ya Hussein", in reference to a revered Shia figure.

In July 24 suspected ISIL members were sentenced to death for their alleged role in the killings [Nabil al-Jurani/AP]

Source: Al Jazeera