In a hilly desert just outside Kabul, three small caves dug into a sandy slope have yielded more than a dozen skeletons, some with bullet holes through the skulls, one still with tufts of hair.
It is suspected there are several such underground chambers and more skeletons -- perhaps hundreds, says the city's criminal investigation chief, Alishah Paktiawal, although this has yet to be confirmed.
The latest mass grave to be unearthed in Afghanistan -- there are about 20 known sites, human rights groups say -- was shown to police more than a week ago by a man in his late 40s.
He told media he had first seen it 12 years ago, before migrating to Iran where thousands of Afghans waited out the 1992-1996 civil war and the harsh Taliban regime that followed.
The grave in Chimtala, just 3km off the main road that leads northwards out of the city is located on the site of weapons bunkers dating back to the 1979-1989 Soviet occupation.
The extent of its contents are still a mystery, as are the identities of the people buried there and when they were killed -- perhaps during the occupation, which was met with fierce resistance, or the subsequent civil war among resistance factions.
Either way, it is another grim reminder of decades of war in which more than a million people were killed, thousands more went missing and a country was destroyed.
It is too early to say what happened at this barren place, interior ministry spokesman Zemarai Bashary said.
"Our teams are working on the case. Once they finish their work, we will know how many bodies were buried there, how old the grave is and also how they were killed," he said.
President Hamid Karzai has appointed a commission to complete an investigation.
"Those innocent people should be remembered in the history of Afghanistan," he said.
"More than 20 mass graves have been found in this country. Some of them are so shocking, like one in Kunar containing 1,200 victims," said Nader Nadery, from Afghanistan's Independent Human Rights Commission.
The Kunar grave in the northeast of the country dates from the 1980s but, again, little is known about the remains inside.
"It's believed a large number of people killed in the 1980s' conflicts are lying in mass graves. Some of them are identified and some are still to be found," Nadery said.
Mass graves cover all the periods of Afghanistan's conflict, said Richard Bennett, head of the human rights unit of the UN mission here.
This includes the communist, or Soviet time, the chaotic rule of the resistance, or mujahedeen (holy warriors), and the 1996-2001 Taliban regime, he said.
"We would like there to be a mapping of these and proper security for all of them and preservation of the human remains," he said.
This would allow eventual forensic investigation to find out who was murdered and why.
The graves also hide atrocities that human rights groups want exposed.
"Many of these people have been executed and there is a question of ultimately finding out the truth and making accountable those responsible, if they are still around and if they can be identified," Bennett said.
He said it was "essential" the skeletons remain undisturbed until they can be investigated.
Paktiawal appeared to think differently when, in front of journalists, he put some of the Chimtala bones into a plastic bag last week and took them back to his office.