A 19-year-old girl is stabbed to death — allegedly by a group of young Satanists who thought she personified the Virgin Mary. Her 16-year-old companion, no longer considered a reliable sect member, is killed and buried alongside her.

The discovery last week of the two victims' burial place has sparked an investigation into a metal band scene in Milan and its possible links to Satan worshippers, according to details that emerged Tuesday.

The disappearance of Chiara Marino and Fabio Tollis in 1998 had remained a mystery until earlier this year, when one of the people later accused of the murders began to cooperate with authorities.

Prosecutors now suspect an occult sect (search) carried out the killings in a drug-fueled ritual, said Francesca Cramis, lawyer for one of the four people arrested in the case.

Its members belonged to a heavy metal band, "Beasts of Satan," and frequented a heavy metal bar in Milan called "Midnight," said Cramis, speaking by telephone with The Associated Press.

Marino was close to the group, and investigators found her room decorated with black drapes, candles and a fake skull.

In January 1998, members of the sect took Marino and Tollis to woods near Somma Lombardo (search), northwest of Milan and killed them in an apparent Satanic ritual (search), investigators say.

According to police, they had already tried — and failed — to kill the two by burning them alive in a car on New Year's Eve, said Cramis.

One of those arrested was Andrea Volpe, the former boyfriend of a third victim, Mariangela Pezzotta, buried alive after being shot in January.

It was the probe of her murder that led authorities to the buried remains of Tollis and Marino.

Prosecutors declined to talk with reporters Tuesday.

"Leave us to work — this probe is delicate and we need to proceed with a lot of caution," Prosecutor Antonio Pizzi said.

Authorities are investigating whether the killers are part of a wider network of Satanists and were taking orders when they killed and offered up their victims.

Oreste Benzi, a priest who works to rehabilitate Satanists, estimates that these worshippers of the occult number around 600,000 in Italy.

"Satanists and those belonging to the occult are often unsuspected people and their goal is morally and psychologically destroy whoever works against them," Benzi told the Vatican's missionary news service Fides. "Often it is the most defenseless people who fall into the net of the sect," he said.