Iraq has sentenced 14 people to death by hanging for their role in the Islamic State group massacre of hundreds of army cadets in 2014, judicial officials said Thursday.

The massacre, one of the worst committed by IS in Iraq, saw the extremists in June 2014 abduct up to 1,700 mainly Shiite cadets from the Speicher military base in the Tikrit region and execute them.

The Al-Rusafa Criminal Court in the capital Baghdad "issued death sentences against 14 criminal terrorists for their participation in the Camp Speicher massacre in 2014", the judicial authority said in a statement, without specifying their nationalities.

The 14 men have 30 days to appeal the sentence. Decrees authorising executions must also be signed by the president.

In 2016, 36 men were hanged for their participation in the massacre.

The Speicher massacre took place in the early days of the group's offensive in Iraq, when its forces seized the second city Mosul and turned it into its stronghold -- until it was driven out by the Iraqi army and an international coalition in 2017.

According to propaganda images released by IS, the jihadists executed the recruits one by one.

Some bodies had been thrown into the Tigris River, which runs through Tikrit, while others were buried in mass graves.

The massacre prompted a surge of Shiite volunteers to enlist in militias fighting the jihadists.

While Iraqi authorities do not give figures, several thousand people accused or convicted of IS links are detained in Iraqi prisons.

The United Nations estimated in 2018 that more than 12,000 Iraqi and foreign "combatants" were being held in Iraqi prisons.

Iraq has been previously criticised for carrying out hundreds of what rights groups say are fast-track trials using confessions obtained under torture or without proper defence.

In 2021, Iraq executed 17 people for all crimes, according to rights group Amnesty International.