Using the Gaza war as their excuse for hate, a group called "Vita Est Militia" signed the posters.
The poster says explicitly "non comprare dagli ebrei!" which means "Do not buy from Jews!"
Here is a translation of part of it (h/t JM):
Boycott Israel!
Contribute to ending the massacre of the Palestinian people!
The boycott of every kind of Jewish merchant and product is fundamental to ending the massacre in Palestine. Every industry, factory, and shop owned by Jews dedicates a percentage of its turnover to Israel, in order to supply it with weapons and in order to continue killing people that have the right to live in their own homeland! To buy from these DISGRACES is to contribute to the killing of thousands of women, children and senior citizens, that have to struggle to stay on a land, a land stolen with violence that is transforming every street into a trench, raping women, burning babies and destroying homes. To avoid the continuation of this:
DO NOT BUY FROM JEWS.
Ironically, this explicitly antisemitic poster is illustrated with a cartoon by antisemitic artist Latuff that claims that any criticism of Israel is silenced by calling it antisemitism.
A couple of weeks ago, there was a spate of antisemitic graffiti in Rome that included swastikas and this one that translates to "dirty Jews:"
The mayor of Rome and many other top officials condemned the acts.