Their sickest video yet: ISIS release footage of their biggest massacre in which prisoners were made to lay in mass graves before being machine-gunned to death

  • Islamic State fanatics release sickening new footage of mass execution
  • The 22minute-long film shows wholesale slaughter of Iraqi military cadets
  • It was filmed at last year's notorious Speicher massacre, in Tikrit, Iraq
  • Men are machine gunned in mass graves, while others are shot in the head
  • It continued into the night and an excavator was needed to shift bodies
  • WARNING GRAPHIC CONTENT

Islamic State fanatics have released one of their most sickening videos yet - new footage of hundreds of military cadets being machine gunned to death while lying face down in the dirt. 

The grisly footage shows executions on an industrial scale, as young men are seen falling from trucks and pleading for their lives before being lay down in shallow graves and sprayed with bullets.

Others are shot individually and their bodies dumped into the Tigris River, while an excavator is seen shifting vast piles of bodies as the executions continue into the night.

The footage reveals the true scale of last year's Speicher massacre, in Tikrit, Iraq, where up to 1,700 military cadets are thought to have been slaughtered.

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WARNING GRAPHIC CONTENT 

ISIS has released new footage showing hundreds of people being killed during the infamous Speicher massacre

A captor lectures the young cadets as they lie bound and gagged in the shallow grave

A captor lectures the young cadets as they lie bound and gagged in the shallow grave

Extremists holding the ISIS flag and machine guns stand over a group of prisoners forced to lie in the dirt

Extremists holding the ISIS flag and machine guns stand over a group of prisoners forced to lie in the dirt

Dozens of prisoners pile off a truck prior to being executed as their armed captors stand guard

Dozens of prisoners pile off a truck prior to being executed as their armed captors stand guard

If body count estimates are correct, the killing of the mostly Shiite Muslims in June last year ranks as one of the worst seen in Iraq in the past decade

If body count estimates are correct, the killing of the mostly Shiite Muslims in June last year ranks as one of the worst seen in Iraq in the past decade

If body count estimates are correct, the killing of the mostly Shiite Muslims in June last year ranks as one of the worst atrocities seen in Iraq in the past decade.

The wholesale slaughter was so vast the graves used to bury the victims could be seen from space.

Highest estimates put at 1,700 the number of cadets ISIS gunmen captured at the Speicher military base near Tikrit and executed at various locations, mostly in the city's former presidential palace complex.

The 22-minute video, posted on jihadist forums, shows some victims pleading for their lives, attempting to explain they had only just joined the security forces.

Around 600 bodies have been exhumed since government and allied fighters retook Tikrit from ISIS in April but many of the victims were dumped into the Tigris river.

An unidentified ISIS leader in military uniform is seen in the video released on Saturday.

He states: 'This is a message I address to the whole world and especially to the Rafidha dogs, I tell them we are coming,' he said, using the pejorative term ISIS employs for Shiite Muslims.

The video was released four days after a court in Baghdad sentenced 24 men to death by hanging over the Speicher massacre.

Dozens of young military cadets are led down to the waterfront prior to being executed

Dozens of young military cadets are led down to the waterfront prior to being executed

The spot where victims were shot and pushed into the Tigris (pictured) has, since Tikrit was retaken, been turned into an improvised shrine

The spot where victims were shot and pushed into the Tigris (pictured) has, since Tikrit was retaken, been turned into an improvised shrine

The trial lasted only a few hours, and the convictions were based mostly on confessions the defendants claimed were obtained under torture.

Combined with a call by the country's top Shiite cleric Grand Ayatollah Ali al-Sistani for Iraqis to take up arms against them, the Speicher massacre played a key role in the mass recruitment of Shiite volunteers to fight the jihadists.

One of the spots where the Speicher cadets were executed is a police building in the sprawling Tikrit palace complex former president Saddam Hussein built in his hometown.

The quay where the victims were shot in the head and pushed into the Tigris has, since Tikrit was retaken, been turned into an improvised shrine.

Relatives, many of whom may never have a body to bury, have streamed to the site over the past two months along with fighters, delegations of officials, students and others. 

The scale of the killings was so vast they continued into the night. Pictured are a group of prisoners blindfolded and forced to lie in the dirt

The scale of the killings was so vast they continued into the night. Pictured are a group of prisoners blindfolded and forced to lie in the dirt

An Islamic State extremist stands over a prisoner during the night-time killings

An Islamic State extremist stands over a prisoner during the night-time killings

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