The killing fields of Iraq: ISIS massacred up to 190 prisoners in just four days, according to analysis of satellite images and horrific pictures posted by jihadistsHuman Rights Watch said Sunni militants executed 160 to 190 men at two locations in Tikrit from June 11 to June 14
Group pinpointed two trenches filled with bodies at first location by cross-checking ground features and landmarks
First execution site located in a field near former palace of the late dictator Saddam Hussein, next to the Tigris river
Other images show prisoners at a second execution site being shot in head, but its position could not be located
HRW director: 'Images from Tikrit provide strong evidence of horrible war crime that needs further investigation'
Iraqi insurgents executed at least 160 prisoners in just four days in the northern city of Tikrit, according to a human rights group which cited analysis of satellite imagery and shocking photographs released by the militants.
The U.S.-based Human Rights Watch said jihadists from the Islamic State of Iraq and the Levant (ISIS) killed between 160 and 190 men in two locations in Tikrit between June 11 and June 14.
The group has compiled a series of graphics documenting the massacres after painstakingly cross-referencing landmarks and individuals from various satellite images with pictures posted online by ISIS.
'The number of victims may well be much higher, but the difficulty of locating bodies and accessing the area has prevented a full investigation,' it said.
After overrunning large swaths of northern Iraq and capturing the cities of Mosul and Tikrit earlier this month, the Islamic extremist group posted graphic photos on a militant website that appeared to show fighters loading dozens of captured soldiers onto flatbed trucks.
They were then forced to lie in a shallow ditch with their hands tied behind their backs while apparently being shot in the head. A final set of photos shows bodies piled up.
Peter Bouckaert, emergencies director at Human Rights Watch, said in a statement: 'The photos and satellite images from Tikrit provide strong evidence of a horrible war crime that needs further investigation.'
The rights group located two of the trenches filled with bodies at the first location by cross-checking against ground features and landmarks in the photographs released by ISIS.
HRW said that using satellite imagery from 2013 and publicly available photos taken earlier, it was able to pinpoint the execution site in a field near a former palace of the late dictator Saddam Hussein, next to the Tigris river.
It said satellite imagery of the site from June 16 did not reveal bodies, but showed indications of vehicles and earth movement consistent with the two shallow trenches visible in the photos.
HRW counted the bodies visible in the available photographs, and estimated that ISIS killed between 90 and 110 men in one trench and between 35 and 40 men in the second.
A further photograph shows a large trench with between 35 and 40 prisoners shot at a second site but Human Rights Watch said it had not been able to pinpoint the site.
Chief Iraqi military spokesman Lt Gen. Qassim al-Moussawi confirmed the authenticity of the pictures on June 15, after they first surfaced, and said he was aware of cases of mass murder of captured Iraqi soldiers in areas held by the Islamic State.
He told The Associated Press at the time that an examination of the images by military experts showed that about 170 soldiers were shot dead after their capture.
Captions on the photos showing the soldiers after they were shot say 'hundreds have been liquidated', but the total could not be verified.
The massacre appeared to be aimed at instilling fear in Iraq's demoralised armed forces - which melted away as militants seized much of the north in a matter of days - as well as the country's Shiite majority, whom the Islamic State views as apostates.
'This is the fate that awaits the Shiites sent by Nouri to fight the Sunnis,' one caption read, apparently referring to Prime Minister Nouri al-Maliki.
The rapid advance of the Islamic State and allied Sunni militants has ignited sectarian tensions, with heavily armed Shiite militias vowing to defend Baghdad and revered shrine cities to the south.
On Thursday, a bombing killed 12 people in a Shiite neighborhood of Baghdad that houses a revered shrine, and police found the bullet-riddled bodies of eight Sunnis south of the capital.
Prominent Shiite leaders are meanwhile pushing for the removal of al-Maliki, who has come under mounting pressure to reach out to the country's disaffected Sunni and Kurdish minorities and rapidly form a unified government following April's parliamentary elections.
Even al-Maliki's most important ally, neighboring Iran, is said to be looking at alternatives.
A senior Iranian general who met with Shi'ite politicians in Iraq during a 10-day visit this month returned home with a list of potential prime minister candidates for Iran's leadership to consider, several senior Iraqi Shi'ite politicians who have knowledge of the general's meetings told The Associated Press on Thursday.
The general, Ghasem Soleimani, is expected to return within days to inform Iraqi politicians of Tehran's favorite, they said, speaking on condition of anonymity to discuss the internal deliberations.
The rapid advance of the Islamic State of Iraq and the Levant in the north as well as the restive western Anbar province has plunged Iraq into its worst crisis since U.S. troops withdrew in 2011 and raised fears of a region-wide conflict.
The radical group has carved out a self-styled Islamic state straddling the Syrian-Iraqi border, where it has imposed a brutal version of Shariah law.
Russia's U.N. ambassador said Thursday that there is a real prospect of a terrorist state springing up from Syria's second-largest city Aleppo to Iraq's capital Baghdad.
Vitaly Churkin, the current president of the U.N. Security Council, said he told the 14 other council members that a terrorist state 'is a very, very serious prospect' that the council needs to address 'because really we are lagging behind... in our responses.'
He argued that Russia's support for President Bashar Assad's government in Syria was aimed at preventing the Islamic State from taking over.
The United States is also looking to Syria, with President Barack Obama requesting $500 million to arm and train moderate Syrian rebels in the hopes of opening up a new front against the Islamic State, which has been at war with other Islamic and secular rebel groups since the start of the year.
The rebel groups turned on the Islamic State because of its alleged brutality toward rivals and activists.
Massacres like the one depicted in the online photos from Iraq could alienate some Sunnis while emboldening the armed forces and Shi'ite militias.
SUNNI PRISONERS 'EXECUTED BY GOVERNMENT FORCES IN REVENGE ATTACKS ON ISIS'
Sunni prisoners are being summarily executed by government forces in much the same way as insurgents have been exacting on captured Iraqis, it was claimed today.
Amnesty International says it has evidence of a pattern of dozens of executions of detainees by Iraqi troops and Shia militias in the cities of Tal Afar, Mosul and Baquba.
Surviving detainees and relatives of those killed gave graphic accounts that suggest Iraqi forces had carried out a series of vengeful attacks against Sunni detainees before withdrawing from Tal Afar and Mosul in northern Iraq, the Amnesty report said.
Amnesty International's Senior Crisis Response Adviser Donatella Rovera, said: 'Reports of multiple incidents where Sunni detainees have been killed in cold blood while in the custody of Iraqi forces are deeply alarming.
'Those among the warring parties in Iraq who are committing war crimes should know that the impunity they currently enjoy won’t last forever and that they may one day be held accountable for their crimes.'
Topic: 'Islamic State' a.k.a. ISIL