Dozens of Iraqis gather in a dimly lit room to scan hundreds of pictures on computer screens -- disfigured images of burnt faces, blown up body parts, beheaded corpses.

All are looking for that one identification mark that could help them recognise whether the picture displayed on the computer screen is of their missing relative for whom many have been searching for months.

"He is not among them," said Fadhila Bustan as she left the room on the ground floor of Baghdad's main morgue.

Bustan, 48, is searching for her 27-year-old son who disappeared last December.

On that day, Mustafa Talib Bustan, a married man with two children, drove off to work waving to his mother, his wife Zainab and the children.

"That was the last we saw of him. He never came back," said Bustan, dressed in a black hijab, a traditional Arabic robe worn by women.

Since then Bustan, sometimes accompanied by Mustafa's wife, has visited the morgue every week, hoping to gather some information of her son, even if only about recovering his remains.

She comes to the room at the morgue where she works through gut wrenching pictures of people slaughtered in Iraq's brutal sectarian attacks.

What adds to her anguish is that Mustafa disappeared at a time when violence in Baghdad had declined significantly on the back of a controversial US military surge.

But then the area where her Shiite family resides -- Haifa Street in central Baghdad -- had always been notorious for being a stronghold of Al-Qaeda led Sunni insurgents.

"During the peak of the sectarian fight we fled to another, safe, area. We returned after the violence dropped and then one day my son disappeared. I am sure he was kidnapped and killed. All I want are his remains," said Bustan.

In December 2007 -- the month Mustafa vanished -- 568 Iraqis were killed across Iraq compared to 1,992 in January the same year. The January toll was the highest since the sectarian strife erupted in February 2006.

Iraq's civilian casualty figures have always been controversial, but a conservative estimate by the British website Iraqbodycount.org puts the death toll at between 83,469 and 91,040 since the US-led forces invaded Iraq in 2003.

The World Health Organisation in a recent report said that between 104,000 and 223,000 died between March 2003 and June 2006 alone, while Iraqis say tens of thousands of people are missing.

The violence that ebbed in late 2007, however, is once again surging and since March the casualties are on the rise.

At least 1,082 Iraqis were killed in March and 1,073 in April, mainly due to fierce clashes between security forces and Shiite fighters in Baghdad, Basra and other Shiite regions of the country.

Although the figures for the dead are available, Iraqi officials have failed to come up with statistics for those missing.

Munjid Ridha Ali, the head of Baghdad morgue, said that in 2007 more than 2,000 unidentified people were buried by the mortuaries in the Iraqi capital, and Shiite holy cities of Karbala and Najaf.

"During the peak of violence we could keep the bodies only for five days in the morgue as there were so many new corpses being brought in daily," Ali told AFP at his office in northern Baghdad.

"Some of the bodies were actually mere pieces of flesh... totally unrecognisable."

The Baghdad morgue is also visited by people from other provinces to see if the bodies of relatives who disappeared elsewhere had been found and brought to the facility.

Raunak Ali from the province of Diyala, north of Baghdad, had travelled nearly 70 kilometres (40 miles) to come to the morgue and look for the remains of her postman brother.

Ranzi Hikmat, 36, was kidnapped in October last year when gunmen in a car ambushed a passenger bus in the town of Khalis in Diyala. The men stopped the bus and abducted the passengers, including her brother.

"I went to the Green Zone ... contacted many government offices but there was no luck. I have still not found him or his body," she said.

The Green Zone, the tightly guarded area in Baghdad, is home to government offices and foreign embassies.

Morgue head Ali said his facility, the largest in Iraq, was still getting bodies of people killed in new violence or even those whose bodies were uncovered in mass graves, some even dating back to the Saddam Hussein era.

"We take photographs of the corpse and other parts of the body and store them so that we can show them to the relatives who come here," he said, adding more and more Sunni Arabs were visiting these days looking for their relatives.

During the height of sectarian conflict, Sunni Arabs restrained from coming to the morgue for fear of being targeted by Shiite militias in tit-for-tat attacks.

The morgue has, however, become the symbol of Shiite and Sunni unity in a city torn by communal hatred.

"Iraqis from different ethnic sects are trying to unite voluntarily," Ali said. "If not, they are forcefully united in the morgue after death."