Members from the student's union, Hobo, uploaded a video of the raid on social media, showing protesters ripping pages out of Salvini's latest book, 'Secondo Matteo. Follia e coraggio per cambiare il paese' (According to Matthew: Madness and Courage to Change the Country), which had hit bookstores on Thursday morning.
The protests came as Salvini visited the city to support local Northern League candidate Lucia Borgonzoni's campaign at upcoming local elections.
While in the city – which is known as a stronghold of left-wing politics and counter-culture – Salvini also paid a visit to its prestigious university.
In the aftermath of the raid the protesters actions were universally condemned.
“Destroying books is in no way justifiable,” Bologna's Democratic Party mayor, Virginio Meriola, was reported as saying in La Repubblica.
“Ideas can only be contested by proposing better ideas.”
Northern League President of Lombardy, Roberto Maroni, went even further, taking to Twitter to brand the protesters as "fascists", before claiming the country's far-right are now "the new partisans".
During Salvini's university visit, a separate group of left-wing protesters also clashed with police while marching along Via Risorgimento.
The protesters carried banners, reading "No racists in the university quarter!” and “Get lost!”, but were pushed back by riot police using shields and batons. Four protesters were injured.