The text on the diagonal red line reads "Berlusconi get lost"
Italian officials have opened an investigation into a Facebook group, "Let's kill Berlusconi", for inciting hatred against the prime minister.
The Italian-language "Uccidiamo Berlusconi" group has more than 16,000 members and is growing in popularity.
Group administrators deny breaking any laws or wanting to harm anyone.
Last month the US Secret Service intervened after a Facebook poll asked people if they thought President Barack Obama should be killed.
Mr Berlusconi's scandalous private life and legal troubles have recently put him at the centre of a heated controversy.
"Let's kill Berlusconi" is just one of several groups established on Facebook in opposition to the Italian prime minister.
Another Facebook group called "Death to Berlusconi" has around 300 members.
No laughing matter
The main anti-Berlusconi group is categorised on Facebook as being "just for fun". Its members openly post messages using their full names.
One person wrote: "Silvio, you'll end up like Kennedy," in an apparent reference to the assassinated US President John F Kennedy.
Despite the administrators' protestations, Italian authorities say the tone of the dialogue places the group on the wrong side of the law.
"These groups foment hate for Berlusconi, they call for his murder," Italy's Justice Minister Angelino Alfano was quoted as saying by Reuters news agency.
"I expect magistrates to do their duty."
Even opposition leader Dario Franceschini, has called for the group to be shut down.
But the site administrators insist there is nothing sinister about the group and have vowed to remove any offensive messages.
In a posting on 12 October, one says: "I personally do not really want to kill anyone, I will not encourage anyone to break the law."