LIMA, Nov 20, 2009 (AFP) - A Peruvian "brotherhood," accused of murdering at least 60 people and selling victims' fat to foreign cosmetics traders, carried out its grisly work undetected for 30 years, Peruvian police said on Friday 20 November.

The gang used abandoned buildings in the Amazon jungle and high Andes to clandestinely butcher victims and "formed a network, or brotherhood that carried out criminal activities," police general Eusebio Felix said.

Peruvian authorities have taken three men and a woman into custody and are hunting two unnamed Italians suspected of buying human fat for as much as 15,000 dollars a liter -- to be used in European cosmetics.

"Those detained have confessed that after assassinating their victims, they slit their throats, hung the torsos and limbs on 'S' shaped hooks," said Felix.

"Later, to extract the fat, they lit candles to heat the room."

The fat would seep out of the thorax of the decapitated bodies and "fell into receptacles for three days and was later decanted."

Jorge Sanz Quiroz, a prosecutor in the case, told AFP "two Italians were implicated. They have been identified but their names cannot be released until they have been captured.

"These people apparently bought the fat from the detainees to sell in European laboratories." One of the Italians is said to have left for Europe.

So far police have found the remains of just one of their victims, but one of the suspects, 56-year-old Hilario Cudena, is said to have told police he committed "various" murders since he was 20 years old.

He is accused of being part of a gang which called themselves the "Pishtacos of Huallaga," a reference to an Andean bogyman said to kill and dismember victims in a region of central Peru.

The gang was uncovered earlier this month when police arrested one person in the possession of 17 liters of human fat, with an apparent value of 255,000 dollars.

But at least one expert has doubts there is a large market in illicit human fat that the gang could have tapped.

Julio Castro, head of the Medical College of Peru, pointed out that plastic surgeons extract fat from their patients every day, but it is not sold.

The fat extracted by the "Pishtacos", he said, would have been riddled with impurities and rendered useless because of their artisanal methods.