Lima - Peru was in shock over allegations that a criminal gang killed people - perhaps as many as 60 - with the motive of rendering the fat from their bodies for sale to companies that make cosmetics.

Some experts have cast doubts on the horror story.

Human fat, once prized for cosmetics and medicinal uses, was collected in past centuries from the bodies of executed prisoners, a dark piece of history that may have inspired the gang.

Serapio Veramendi - one of the alleged members of the gang - made Peruvians shudder over the chance that it might actually be true.

"We used a 'wincha' (tool) to cut off their heads. We hung the dismembered bodies from hooks, and then we lit up six or eight candles under them, and we waited for two or three days to have the fat drip into a bottle," Veramendi, 32, reportedly told police.

Veteran police officers said this was the most macabre story they had ever come across.

The gang called themselves Los Pishtacos. In the mythology of Andean cultures, a pishtaco is a devil that kills people to steal their fat.

Peruvians were wondering just how far human beings are willing to go to satisfy their greed.

"How can there be people who dismember beings with the lone goal of getting money from human fat?" Peruvian Interior Minister Octavio Salazar wondered in shock.

Veramendi was arrested this week with three accomplices, after a routine police raid on buses travelling from the provinces to Lima found lemonade bottles filled with fat that later laboratory tests proved to be human. The bottles had been sent as packages to be delivered.

"It was sample material," Veramendi explained.

He claimed that the gang had already collected 17 litres of fat that they were hoping to sell to cosmetics firms - some of them allegedly in Europe - for 15,000 dollars per litre.

Indeed, authorities found such a supply of fat at the home of another alleged pishtaco, Elmer Castillejos, in a village in the central Peruvian province of Huanuco, about 400 kilometres north-east of Lima.

Seven suspects remain at large.

Even if some police doubt the story, criminal investigations director Eusebio Felix stressed that authorities believe that there were indeed some killings like the ones that Veramendi described.

Felix noted, however, that it was not immediately possible to say how many people had been killed by the gang.

"You obviously cannot trust a criminal, but we have found sufficient evidence to be almost 100 per cent sure that we are facing a case of pishtacos," he said.

Police fear that the gang may have been active for years, perhaps as long as two decades, and do not rule out possible involvement in disappearances over the years of about 60 peasants in Huanuco and the neighbouring province of Pasco, in the mountains, where the arrested suspects lived.

Still, Peruvian Medical Association dean Julio Castro Gomez remains unconvinced of the story.

He notes that plastic surgery clinics obtain large amounts of fat in liposuction procedures and discard it because there is no market for it. Plastic surgery clinics sometimes do use fat to fill in wrinkles, but they extract the patient's own fat from another part of the body for that purpose.

Why then would anyone pay 15,000 dollars per litre?

Besides, while Castro Gomez admitted that fat could be rendered out through makeshift procedures like the one that Veramendi described, he explained that it would be full of impurities and thus useless.

Police were still working to determine what happened, particularly in the face of evidence that at least one victim - a 27-year-old man - was indeed killed and his body defiled in this way. (dpa)