Portuguese authorities on Tuesday extradited neo-fascist Italian national Maurizio Tramonte to Italy to service a life sentence for his involvement in a deadly bombing.

Tramonte and fellow neo-fascist Carlo Maria Maggi were convicted in 2015 for the 1974 bombing in the northern Italian city of Brescia's Piazza della Loggia, which targeted an anti-fascist trade union rally.

At least eight people were killed and more than 100 others injured in one of the largest attacks to take place during Italy's turbulent "Years of Lead" between the 1960s and 1980s. Many of the victims were teachers and laborers.

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Following the 2015 conviction, Tramonte traveled to Portugal in an attempt to eventually flee Europe. Earlier this year, he was arrested by Portuguese police on a European arrest warrant.

Manlio Milani (center), who lost his wife in the Piazza dell Loggia attack, has fought for decades to ensure justice is served

The 'white coup'

Tramonte was one of several members of the Italian far-right paramilitary group "New Order," which committed several public attacks in a bid to trigger a military takeover dubbed the "white coup" and restore fascist rule.

While far-left terror groups opted for committing targeted assassinations of political leaders at the time, far-right organizations used a strategy that emphasized numerous casualties, bombing public squares, trains and railway station.

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At least 428 people were killed and thousands more injured during politically-motivated attacks committed during the "Years of Lead," according to figures from the Italian Association of the Victims of Terrorism.

Many of those who committed attacks during this time fled Europe, while others sought asylum outside Italy, including in countries such as France and Nicaragua.