Saddam Hussein’s former palace complex here is seemingly idyllic, its gardens lined with lush palm trees and bursts of bougainvillea. But at the heart of the verdant compound, diggers are turning over the earth in search of evidence from what could be one of Iraq’s worst atrocities in more than a decade.

Iraqi authorities say that the palace complex could contain the remains of hundreds of young soldiers slain by Islamic State militants last June. As many as 1,700 Shiite soldiers from nearby Camp Speicher were killed by jihadists, a massacre seared into the national consciousness.

Since Iraqi government teams started the excavation this month, they have uncovered more than 160 bodies of young men, most of whom had been bound, shot and then buried in mass graves.

For months, relatives have waited for news of their loved ones who went missing at Camp Speicher. Now the bodies exhumed in Tikrit, which are awaiting DNA testing at Baghdad’s central morgue, offer some of the first concrete evidence of one of the most grisly crimes committed by a group already known for its shocking brutality. Officials say identification cards found on several of the bodies bear names that match reported victims from Camp Speicher.

“We gave our samples to the morgue, and now we are waiting to hear if they found my brother or not,” said Abdullah Mohammed, who saw his younger sibling, Saad, gunned down in a video posted by the Islamic State to social media sites after the massacre. In a telephone interview from his home town in southern Iraq, Abdullah began to cry.

“We’ve seen a lot of bodies,” he said. “But we don’t know if they are him. The government hasn’t told us anything.”

Iraqi forces backed by Shiite militias wrested Tikrit back from the Islamic State last month, after a weeks-long offensive supported by U.S.-led airstrikes. The jihadists had seized the city — which is Hussein’s home town — last June. In the chaos of the assault, thousands of recruits from Camp ­Speicher donned civilian clothes and slipped away from the base in the hope they could escape.

But they soon encountered well-armed Sunni militants from the Islamic State, who separated the recruits by sect and hauled the Shiite soldiers off to the vast complex of riverside villas built by Hussein before he was overthrown in the 2003 U.S. invasion.

The jihadist gunmen spent the next three days in an industrial-scale killing spree that the United Nations says probably amounts to a war crime. The militants boasted about the bloodbath, saying they killed 1,700 soldiers, and circulated videos and photographs of the executions online. Later, through satellite imagery, New York-based Human Rights Watch estimated that as many as 770 people had been killed at various sites at the palaces on June 12 and June 13 last year.

Iraqi officials, even months after the assault, admitted that they did not know exactly what happened to the cadets.

The search

Now, using shovels and scalpels, and taking short breaks for bread and sweet tea, dozens of government workers are toiling 12-hour days in the heat to get justice for these Iraqis.

Inside the palace complex, there are 10 locations that officials have identified as possible mass gravesites. There are an additional three that they say they still need to test inside the city. The diggers, in bright blue scrubs and surgical masks to block the stench, have made gruesome discoveries: legs without torsos, tufts of hair and crumbled bones they collect in clear plastic bags.

On a recent afternoon, one worker who was digging deep inside a mound of earth and rocks had just found parts of what he thought was the same body. He struggled to shove a fibula — or shinbone — back into a tattered pant leg to keep what was left of the corpse intact. Another man with a mask and a clipboard walked in a circle around the newly discovered remains, methodically recording the morbid scene. On the gentle slope of dirt next to him, a severed pair of legs rested.

“This area now is the hardest type of mass grave to dig,” said another Iraqi working at the scene, soil expert Ghanem Abdel Karim. The corpses “are buried at random, and they are under rocks and thick soil. We must make sure we are only digging up one body at a time and make sure pieces of one body don’t end up in the bag of another.”

Karim, who works for Iraq’s human rights ministry, also helped uncover the mass graves left behind by Hussein’s brutal regime. He and his team now search the palace grounds for dirt mounds and bullet shells, indications of possible burial places.

According to survivor testimony and confessions from militants arrested in the city, groups of scores of soldiers were killed and buried in different spots, officials said. Other cadets were shot and pushed into the Tigris River — whose banks in Tikrit are still stained with blood. Some of the bodies later floated downstream, where they were recovered.

At one site at the palace complex, workers exhumed 50 bodies that had been stacked on top of one another and then covered in dirt, officials said. Exhumations are now taking place at a second location: a dry riverbed that cuts through the palace compound.

Most of the victims have been found face-down, their hands tied and bullet holes in their heads, said Zaid Ali, the director of Baghdad’s central morgue. He is sleeping at the palaces so he can rise each morning and resume supervision of the digging.

Workers have found bodies with identification cards, cellphones and small bills. One corpse was found with a tiny book of prayers.

But with decrepit forensic equipment — and with gunfire and explosions echoing from clashes nearby — the workers say the recovery of the bodies is a painstaking task that could take weeks or even months to complete.

“It’s not secure; it’s a war zone,” Ali said of Tikrit, where Iraqi security forces are still battling the jihadists in isolated areas. “So this makes the work much more difficult.”

“This is a historical moment,” Mohammed al-Timimi, an official from the Iraqi prime minister’s office, told the workers at the site. “There is no work more honorable than the work you are doing now.”

Mustafa Salim contributed to this report.

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