Confessions from Shiite militiamen led Saturday to the discovery of 15 more bodies dumped in mass graves south of Baghdad, officials said — the second such find this week.

Women holding family photos rushed to the muddy field in Mahmoudiya in hopes of finding missing loved ones as new information emerges on past sectarian bloodletting.

The grisly discovery came two days after the Iraqi troops found the remains of 30 people believed to have been killed more than a year ago buried in three abandoned houses elsewhere in the area.

Mass graves have been turning up with increasing frequency as American and Iraqi military operations have cleared former militant strongholds, allowing troops to step up patrols in previous no-go zones.

But the others have all been mainly in Sunni areas in Anbar province to the west and Diyala to the north of the capital.

The U.S. military said the mass graves unearthed in Mahmoudiya were the first found in the area south of Baghdad, long known as the triangle of death before a recent decline in violence.

The remains were found after recently detained militia leaders confessed to killing dozens of Sunnis as well as Shiite rivals and burying the bodies in the abandoned houses and adjacent fields, according to Iraqi army and city officials.

The find offered new evidence of the atrocities carried out by Shiite death squads that were known for their trademark kidnappings and execution-style killings until they were reined in by an Aug. 29 cease-fire by anti-U.S. cleric Muqtada al-Sadr, the leader of Mahdi Army militia.

Bullet-riddled bodies continue to turn up on the streets of Baghdad and other cities, but the numbers are now in the single digits instead of the dozens. An ongoing violent standoff between al-Sadr's fighters and U.S.-backed Iraqi troops has raised concerns the truce could be at risk.

Thirteen of the bodies found Saturday had been dumped in one grave about 500 yards away from the local office of al-Sadr's movement, while two others were buried together in a nearby area, city spokesman Ather Kamil said.

An Iraqi army officer, who spoke on condition of anonymity because he wasn't authorized to release the information, said Shiites also were caught up in the violence but most of the victims were believed to be Sunnis.

Neighbors said it was common knowledge that the Mahdi Army used the three abandoned houses in which the remains were found Thursday as detention centers but nobody asked details about what was happening inside.

"The Iraqi forces found many decomposed bodies in this house and I think that these dead bodies have been here for a long time and cannot be identified," said resident Shihab al-Azawi.

Authorities said they have so far been able to identify only two sets of those remains — a 22-year-old Sunni woman whose clothing was recognized by a nurse at the hospital and a 31-year-old Sunni municipality worker who still had his ID. Their families have fled the area.

In the vast majority of missing person cases in Iraq, relatives are left guessing forever about what happened because Iraqi officials usually lack such forensics aids as DNA and dental records. The killers  also typically removed the IDs after killing their victims.

But desperate women and children wailed and waved photos, hoping for any sign of their missing loved ones, as they surrounded the Iraqi troops who exhumed the bodies on Saturday.

U.S. soldiers provided cover and helicopters buzzed overhead. Other Iraqi soldiers continued to comb the palm tree-lined desert area, apparently looking for more bodies.

It could not be determined if other bodies had been identified by relatives on Saturday.

Mahmoudiya, a predominantly Shiite city of some 600,000 people, sits in an area about 20 miles south of Baghdad.

Sunnis comprise about 20 percent of its population, but many families have moved to escape the sectarian cleansing campaign, and their houses often were torched and belongings scattered.

An Associated Press tally shows that at least 662 bodies have been unearthed in mass graves since May 29, 2007 — about half of them this year.

All but the 45 found this week were in predominantly Sunni neighborhoods in Baghdad and al-Qaida strongholds to the north and west of the capital.

PHOTO CAPTION 

Policemen place the remains of bodies found in a shallow mass grave in Mahmoudiya, 30km (19 miles) south of Baghdad April 12, 2008.

AP