An Italian man who allegedly beheaded a Ukrainian maid before being shot dead in Rome by police was a delusional pro-Israel extremist who used to take Quaaludes (Methaqualone), the so-called Wolf of Wall Street drug, according to local media reports.

Federico Leonelli, 35, killed 38-year-old Oksana Martseniuk by stabbing her at least 40 times. Then he beheaded the woman in an attempt to chop the body into pieces and get rid of the corpse in black plastic bags.

Lionelli was eventually shot dead by police outside a gated house in Rome's Eur neighbourhood.

According to Giovanni Ciallella, the owner of the house where Leonelli had been staying since June, the lodger said he was "ready to join the Israeli army against Hamas and terrorists armed with missiles" after discovering his purported Jewish roots and meeting a rabbi in Rome.

"He started to study the Torah, the Talmud and once he stopped to talk about the Old Testament with me." Ciallella, who also worked with Lionelli 10 years ago, told La Repubblica newspaper.

"Then he searched on the internet and checked out dozens and dozens of videos. At night he watched films by rabbis at full volume which informed him of what was happening in the Gaza strip," according to Ciallella, who worked with Leonelli 10 years ago in the IT sector.

Leonelli was suffering from depression after the death of his girlfriend and was supposed to stay in the house until early September. Ciallella agreed to host his old friend over the summer in a building divided from the main house. But Leonelli did not leave the house in two months, spending all his time in the room.

The lawyer of Leonelli's sister, Giuseppina Tenga, said the man was being treated by a psychiatrist and used to take the sedative and hypnotic drug methaqualone, also known as Quaaludes - the drug made popular by Jordan Belfort's book The Wolf of Wall Street, and the Martin Scorsese film starring Leonardo Di Caprio.

"The doctor had told Leonelli to stop taking the drug but in the past he ignored him. He even ordered methaqualone on the internet and the doses he was taking could cause hallucinations," Tenga said.

Quaaludes are a synthetic, barbiturate-like, central nervous system depressant used as a hypnotic for the treatment of insomnia and as a sedative and muscle relaxant.

One drug sequence in Wolf of Wall Street features Jordan Belfort (Di Caprio) and his best friend (Jonah Hill) taking an excessive amount of Quaaludes and suffering the consequences.