Italian police on Monday arrested 12 leading Juventus hardline fans as part of a major investigation into violence and extortion linked to match ticket sales.

The suspects are accused of criminal association, aggravated extortion, money laundering and violence, police said.

The arrests were the culmination of a year-long probe centred on the alleged blackmail of ticketing officials by the “ultras”, who wanted cut-price blocks of tickets they could sell to fellow fans.

They reportedly began threatening to sing racist chants during matches - which would lead to the club being hit with fines and possibly having points deducted - after Juventus stopped distributing blocks of tickets for resale in 2017, Italian media said.

Police said the hardcore groups had set up a “widespread criminal strategy to ‘restore’ lost favours”.

Those arrested included the heads of the Drughi, Tradizione-Antichi Valori, Viking, Nucleo 1985 and Quelli ... di via Filadelfia groups, police said in a statement.

Prosecutor Patrizia Caputo described the Drughi as “a military organisation”, saying that “even the most trusted members were got rid of if they did not follow the orders of the undisputed leader”.

“Violence is a way of life for these people. Not even the presence of children stopped them,” she said at a press conference, describing how innocent fans would be bullied into giving up their paid-for seats in the stadium.

Officers were carrying out 39 search warrants targeting those arrested and other suspects, with the help of police from cities across northern and central Italy, from Alessandria to Bergamo, Florence, Genoa and Milan.