The blackened fragments spread out on the table look at first glance like no more than a scattering of charcoal, left over from a long-dead fire.

But on closer examination one sees that the fragments are grouped, and that each group has its own printed label.

The labels start at the top of the table: cranium, for a handful of shell-like shards, followed by upper limb, ribs, vertebrae, pelvis, lower limb and, at the very bottom, hands and feet.

In one corner, in a plastic lunchbox-type container with a see-through lid, and cradled in tissue paper, are the smallest fragments of all.

Despite the blackening, most of them still look exactly like what they are: human teeth.

The fragments are what the National Prosecuting Authority believes could be the remains of Siphiwo Mthimkulu, Topsy Madaka and the Pebco Three, anti-apartheid activists murdered by the security police in the 1980s.

And for at least the next week and a half, they will be housed in an anatomy laboratory at the University of Cape Town's medical school, undergoing examination by a team of experts.

According to the version given to the Truth and Reconciliation Commission (TRC) by the policemen, the abducted activists were taken to Fort Chalmers, an abandoned police post near Cradock in the Eastern Cape.

There they were drugged, shot, their bodies burned on a diesel-soaked pyre, and the ashes dumped in the nearby Fish River.

In 2007 the NPA's missing persons task team oversaw an excavation of the site of the fire, and also drained a nearby septic tank.

Shock at finding remains

Team leader Madeleine Fullard told journalists at a briefing at the medical school on Wednesday that the investigators, who included archaeologists and forensic anthropologists, removed some 260kg of material from the site for closer examination. This included charcoal, fragments of burnt tyres and bone, as well as bullets and a bunch of keys.

Once this had been sorted by hand, they were left with just over 12kg of burnt bone — a major surprise to the team members, who had been expecting at most a small bone or tooth that the killers missed when cleaning up after their grisly deed.

"We're still kind of in shock that we found these remains at all," Fullard said.

The collected bone was now being examined in an attempt to link it with individual activists, or at least to say how many people it came from.

Over 60 teeth had already been examined by a forensic odontologist, or tooth expert, who had submitted his report.

The bone examination was being done by experts including forensic anthropologists Claudia Bisso, an Argentinian who has been involved in locating remains of victims of state death squads in that country, and Steven Symes, from the United States, an expert on trauma in bone.

Closure for the families

Fullard said the result of the odontological report and the bone findings would be discussed with the family members of the slain activists before they were made public.

Asked when this would be, she said: "We anticipate within weeks."

But it could be longer if the team decided to attempt DNA analysis of some of the bones.

Fire had a destructive effect on DNA in bones, and testing in a similar case, that of the Mamelodi Ten, had so far been "mixed and inconclusive".

"So it's probably not a very hopeful scenario," she said.

However the remains were uncovered at the site pointed out to the TRC by the perpetrators.

If the results of the bone examination were consistent, there would be a "strong case" that the remains were of the slain activists.

"At this stage we don't have anything to contradict that," she said.

One of the team's main goals was to recover identifiable remains for families to bury.

Some of the families had said they would be happy to have only one bone to bury; all Mthimkulu's mother had so far been able to bury was some of his hair, which fell out after he was secretly poisoned by the police.

Fullard said though the probe was still in an investigation phase, and had drawn no conclusions, several discrepancies had come to light.

It seemed clear, from the quantity of bone recovered, that the activists' ashes were not thrown into the Fish, as the security police maintained at their TRC hearings.

Given their version that it took up to eight hours to burn the bodies, it seemed unlikely on a practical level that those hot ashes could be scooped into black plastic bags, as the police claimed, to be taken to the river.

The police had also said they did not consume alcohol at the burning, yet the investigators had found a large quantity of green bottle glass fragments there.

Asked about the presence of the fragments of burned tyres, Fullard said the perpetrators had in their TRC hearings specifically denied using tyres to burn the bodies.

Symes said that laying out pieces of bone in categories helped investigators see whether any of them were duplicated, which would indicate that they came from more than one body.

At this stage, he said, "we have more than one".

Four former security policemen were granted amnesty for the Mthimkulu/Madaka killings; only two of the eight involved in the Pebco matter got amnesty.

Sapa