Skeletons, many wearing clothes and blindfolded, jut out from the desert sands in southwestern Iraq where forensics experts have unearthed at least two mass graves of victims from the brutal suppression of a 1991 Shiite uprising.

The chief investigative judge in Saddam Hussein's trial said they have documented evidence of more than 100,000 victims of the crackdown against Shiites in the wake of the 1991 Gulf War and unofficial accounts showing the number could be as high as 180,000.

"When the whole search is done, we could announce a number of mass graves and of victims," Raid Juhi said during a visit Saturday to the grave sites, according to a pool report. "Some people were loaded on buses and taken somewhere and those vehicles and buses came back with no people on them."

Saddam and seven co-defendants are currently on trial for the killings of more than 140 Shiites following a 1982 assassination attempt against him in the town of Dujail -- the first of what Iraqi authorities say could be up to a dozen proceedings. Saddam could face death by hanging if convicted in the Dujail case. But President Jalal Talabani, a Kurd, has said he doubted any sentence would be carried out until all trials were complete.

CountryWatch: Iraq

Juhi said there were more than 70 defendants in custody in connection with the 1991 Shiite uprising, including some who were in key positions during the former regime and others in minor positions.

He would not provide names, except to say that Saddam and his cousin, Ali Hassan Majid, or "Chemical Ali" had been questioned by the investigation team.

Meanwhile, forensics experts and archaeologists are painstakingly searching for remains to provide direct evidence to the Iraqi High Tribunal, which is overseeing the cases against Saddam.

"This whole project is for the 1991 uprising and the killing of the Shiite people," said Michael Trimble, a 53-year-old forensic psychologist from St. Louis, Missouri, who set up camp with about 120 people amid heavy security about three weeks ago. "We've located two sites so far and we are in the process of testing, I think 22."

He said the killings were carried out in desert areas where those who carried out the killings could throw the victims into shallow embankments or simply shoot them as they were standing inside.

The bodies of 28 men, estimated to be 20 to 35 years old, have been found so far in one of the graves, with small blue, yellow and red flags marking the findings -- including bodies, spent cartridges and bullets. A wrist still bears a watch and plastic bags have been used in some cases to store disarticulated finger bones.

The victims were wearing clothing favored by Shiites, including dishdashas, and most were blindfolded, with the blindfolds appearing to have been fashioned from keffiyehs, traditional Arab headdresses, said Kerry Grant, a 45-year-old Australian forensic archaeologist at the site.

One skeleton was wearing a blue jacket and his hands were behind his back, suggesting they had been tied. A plastic flip flop, a tennis shoe and some skulls with hair on them also could be seen at the site.

"Going by the clothing, I think they were grabbed very quickly," Grant said.

The leaders of the team of about 120 people said they were motivated to keep working, despite searing heat, by their desire for justice for the victims.

"When you work with the remains for a long time, you get very attached to them and you feel very badly for them," Trimble said, adding the remains would be repatriated when they were no longer needed as evidence.

Kerry also expressed regret that the team was unlikely to find all the bodies dumped in the area of about three miles.

"We know there is more in the area, but there is only so much we can do. We can't be here too long," she said.

The second site -- in a ravine about 72 feet deep and 33 feet wide -- had only been under excavation since late last week.