The Italian prime minister has appealed for an end to election campaign violence, as police found a copy of Hitler’s Mein Kampf in the home of a right-wing extremist accused of going on a shooting spree on Saturday, wounding six migrants in the sleepy Adriatic town of Macerata.

Luca Traini, 28, a former local election candidate for the anti-migrant Northern League, remained in jail as police investigated him on multiple counts of attempted murder with the aggravating circumstance of "racial hatred" for the Saturday night attacks.

The five men and one woman who were wounded in the two-hour drive-by shooting spree were from Nigeria, Ghana, Gambia and Mali, according to RAI state television.

Police searching Traini’s home on Sunday found a Celtic Cross flag favoured by neo-Nazi groups and right wing literature including Mein Kampf.

Col. Michele Roberti, the Carabineri commander in Macerata, told Sky TG24 that Traini demonstrated no remorse for the two-hour rampage and "it's likely that he carried out this crazy gesture as a sort of retaliation, a sort of vendetta" for the gruesome slaying of a teenager a few days earlier.