RAQQA, Syria (Reuters) - Sajed Salameh has spent days waiting at a mass grave in the Syrian city of Raqqa, hoping the bodies of his wife and three children will soon be found so he can give them a proper burial.

They were killed along with his father and two other relatives by an airstrike during the U.S.-backed offensive against Islamic State (IS) and their bodies were buried by the jihadists without his knowledge, he said.

By laying them to rest himself, Salameh said he hopes for “peace of mind that we buried them in a specific place”. He has already reburied his father, whose body was exhumed from another mass grave.

One year since Islamic State’s defeat at Raqqa, the bodies are still being counted as they are pulled from mass graves and from the rubble in the city, which had served as the group’s Syrian headquarters.

A team combing the rubble and burial sites has found more than 2,600 bodies so far this year, said Yaser al-Khamis, the team leader. Many more bodies have been recovered by Raqqa residents working on their own, local sources say.

The current focus of Khamis’ team is the “Panorama” site - formerly a public garden where he said some 800 to 1,500 men, women and children are estimated to have been buried. Some 233 bodies have been exhumed there since work began in October. It is believed to be the biggest of nine mass graves.

Salameh looked on as workmen wearing facemasks pulled one body after another from the trenches, some wrapped in blankets, before putting them in blue bodybags.

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“These are the remains of an unknown man, Panorama, October 16,” a worker wrote in marker pen on one of the bags.

Khamis said the site comprises 200 trenches, each 30 metres (yards) long.

Locals say IS prepared the mass graves before the offensive. Some of the bodies belong to militants, Khamis said.

A forensic team stands by to determine the sex, age and cause of death. Those not claimed by relatives are driven away for burial at the city cemetery.

IDENTIFYING THE DEAD

Salameh was not at home when his house in Raqqa’s Hisham Ibn Abd al-Malik area was hit on July 13. He said he was busy at the time seeking medical help for himself and the neighbors’ children who had been hurt in an air strike beforehand.

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The body of Salameh’s father was immediately taken away and buried. The others were pulled from the rubble later on and taken to the IS-held hospital, before being buried by the group.

He hopes to identify his wife and children from the clothes they were wearing at the time they died. “There are pictures of them before the strike,” he said.

Salameh now lives in the nearby town of Tabqa with his surviving daughter. He says a total of 22 people were killed in the air strike including neighbors and first responders.

The fall of Raqqa was a big victory in the war against IS.

But Amnesty International has accused the coalition of failing to admit or adequately investigate “the shocking scale of civilian deaths and destruction it caused in Raqqa”, where IS used civilians as human shields.

The coalition spokesman said the number of civilians so far confirmed as having been killed by accident in the campaign was 104, but he did not rule out that it may go higher. “If there is an allegation of a civilian casualty, we check it against our existing records,” Colonel Sean Ryan told Reuters.

Amnesty’s senior director of global research said this month the majority of some 2,500 bodies unearthed in Raqqa were believed to be civilians who died in air strikes.

The coalition has said its operations have used deliberate targeting to minimize the impact on civilians.