Updated at 2:49 p.m. Eastern.
ROME - Italian Premier Silvio Berlusconi is under investigation in a prostitution case involving a then-17-year-old Moroccan girl.
Berlusconi has dismissed the investigation by saying prosecutors are just jealous they weren't invited to his home for dinner.
In a statement Friday, Berlusconi called the investigations "absurd" and noted he has been investigated over 100 times, yet never convicted.
Berlusconi's lawyers confirmed Friday that he is under investigation in the prostitution case, which they called "absurd and groundless."
Nicolo Ghedini and Piero Longo said the probe represented a "very serious interference in the prime minister's private life."
They said the allegations "have already been refuted by all witnesses and people directly involved."
Italy's leading newspaper, Corriere della Sera, said the 74-year-old premier is suspected of having sex with the minor and then abusing his power in trying to cover up the encounters with the girl, nicknamed Ruby.
The case became public months ago, when it emerged that Berlusconi had intervened to secure the release from police custody of the girl, who had previously been at his villa.
Berlusconi said at the time that he had done nothing wrong, and that he had only intervened to help someone in need. The girl denied having sex with the premier.
Last month, Rome after Berlusconi pulled off another astonishing escape from political death, scraping through two confidence votes in a dramatic parliamentary showdown.
But the Italian leader's hold on power remains precarious after his razor-thin victory made political gridlock a near certainty - and the violent street protests showed growing unease with his rule.
Masked protesters torched cars and trash bins, smashed shop windows and clashed with police. Clouds of white tear gas and orange flares engulfed streets, as shops full of Christmas goods hurriedly closed down. Employees at one bank cowered in fear as a group of stone-throwing youths swept by.
Protesters rampaged in the area around parliament and Berlusconi's residence, which had been cordoned off by heavy police presence. By sundown, almost 100 people, both protesters and police, were reported injured, including about two dozen hospitalized. About 40 were reportedly taken into police custody.
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