Police in Brazil believe a boy who massacred his family before killing himself was driven by an obsession with the 1974 Amityville murders.

The boy, identified as Marcelo Pesseghini, reportedly killed his parents, both police officers, as well as his grandmother and great-aunt in the city of Sao Paolo.

The victims were shot in the head with a .40 calibre weapon according to police, who believe the massacre began on Sunday night and continued into the early hours of Monday.

CCTV footage suggests Marcelo went to school the day after murdering his family, and killed himself that night. The boy reportedly drove his mother's car to school and stayed inside the vehicle for five hours before attending his classes.

"We believe the revolver was a police gun and was taken from his father," Military Police commander Colonel Roberto Benedito Meira told O Globo TV, adding: "At least five shots were fired inside the house, all compatible with a .40 pistol."

The boy's 40-year-old father Luiz Marcelo Pesseghini, who had served in the police force for 19 years, was found dead on his bed. Mother Andreia Regina Pesseghini, a 36-year-old serving in the Military police, was found on her knees in the bedroom.

The grandmother and great-aunt, who lived in a semi-independent section of the same house, were also found on their respective beds.

The father's service revolver was found close to Marcelo's body. A second gun, .32 calibre, was recovered from his school bag.

The possibility of an external attacker has been dismissed, as there was no ransacking or forced entry.

"Everything seems to indicate Marcelo killed his parents and relatives," Itagiba Franco, of the Sao Paulo Civilian Police's homicide department, told a press conference, according to the Mail Online.

Amityville link

Last December Marcelo posted a photograph on his Facebook page of the Amityville case, in which a boy killed his parents and four siblings. It was later claimed that the house was haunted by the victims.

The Sao Paolo case appears to bear a strong similarity with Amityville, given that both incidents involved the massacre of a family and were perpetrated by a child.

A friend of Marcelo testified to the young boy's fascination with killing people, telling police: "He always told me he wanted to become a hired killer.

He had a plan to kill his parents during the night, so that no one would notice and escape in the parents' car and live in an abandoned place."

However this view was disupted by Marcelo's cousing Sandra Alves Feitosa, who told local media: "If it was a Marcelo who did it, then it was a force of evil. He was a boy who was loving and loved by all. He never even got into a fight at school."