Forensic teams in Ciudad Juarez in Mexico are unearthing more than 4,000 bodies buried in common graves.
A local government official said DNA samples from the bodies would be compared to those of missing persons.
It is thought that some of the bodies could belong to women killed in a wave of unsolved murders that began in the city in 1993.
The official said the corpses were buried in common graves because they had not been claimed after 90 days.
The bodies being exhumed were buried between 1991 and 2005 - all unclaimed bodies buried since 2005 have been identified first.
More than 300 women have been murdered in the town in Chihuahua state since 1993, and an unknown number have gone missing.
There is no generally accepted motive for the killings.
They have been variously attributed to serial killers, drug cartels and domestic violence. Some of the killings are believed to have been sexually motivated.
Many of the victims were poor working mothers employed in factories in the industrial city, which is on the border with Texas.
There have been several arrests, but the killings have continued.
BAGHDAD (AP) — Religious vigilantes have killed at least 40 women this year in the southern Iraqi city of Basra because of how they dressed, their mutilated bodies found with notes warning againstviolating Islamic teachings,the police chief said Sunday.
Maj. Gen. Jalil Khalaf blamed sectarian groups that he said were trying to impose a strict interpretation of Islam. They dispatch patrols of motorbikes or unlicensed cars with tinted windows to accost women not wearing traditional dress and head scarves, he added.
The women of Basra are being horrifically murdered and then dumped in the garbage with notes saying they were killed for un-Islamic behavior,Khalaf told The Associated Press. He said men with Western clothes or haircuts are also attacked in Basra, an oil-rich city some 30 miles from the Iranian border and 340 miles southeast of Baghdad.
Those who are behind these atrocities are organized gangs who work under cover of religion, pretending to spread the instructions of Islam, but they are far from this religion,Khalaf said.
Throughout Iraq, many women wear a headscarf and others wear a full face veil although secular women are often unveiled. Since the overthrow of Saddam Hussein and the rise of a Shiite-dominated government, armed men in some parts of the country have sometimes forced women to cover their heads or face punishment. In some areas of the heavily Shiite south, even Christian women have been forced to wear headscarves.
Before the U.S.-led invasion in 2003, Basra, Iraq’s second-largest city, was known for its mixed population and night life. Now, in some areas, red graffiti threatens any woman who wears makeup and appears with her hair uncovered:Your makeup and your decision to forgo the headscarf will bring you death.
Khalaf said bodies have been found in garbage dumps with bullet holes, decapitated or otherwise mutilated with a sheet of paper nearby saying,she was killed for adultery,orshe was killed for violating Islamic teachings.In September, the headless bodies of a woman and her 6-year-old son were among those found, he said. A total of 40 deaths were reported this year.
We believe the number of murdered women is much higher, as cases go unreported by their families who fear reprisal from extremists,he said.