I spotted an article in Polish webnews site: link, link
And also some links in other languages: Repubblica, Repubblica2
Sorry, couldn't find any english article about this, but here is a short
It says that it was discovered that out of 683 assistants working for
Italian MEPs, only 54 had work contracts, and others where working
And the parliament secretariat set a deadline on 13 May for MEPs to sing contracts with their assistants, but only about 250 have done so. So others where banned from 13 May from entering the Parliament, and had their blue cards invalidated, but the article says that the remailing assistants are still entering the parliament, as "guests". The EP administration is thinking about introducing some penalties for this.
Schwarzarbeit auf Italienisch? lavoro nero. Wieder was gelernt.