The incident looks certain to jolt campaigning for a March 4 national election, with a centre-right alliance that leads in the polls promoting a fiercely anti-migrant programme.
The suspect, named locally as Luca Traini, 28, had an Italian flag wrapped around his neck when he was detained.
Gentiloni said Saturday that "one thing is certain, that horrendous crimes and criminal behavior will be prosecuted and punished".
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Christian Eriksen celebrates scoring Tottenham's goal after 11 seconds against Manchester United at Wembley. Continually he has the same injury - the lateral (knee) ligament '. "The first goal was a fantastic goal".
The chief suspect in that case is a Nigerian.
He said: "Stay at home until further notice".
Macerata Mayor Romano Carancini confirmed that five foreign men and one woman, all black, were wounded in Saturday's shooting spree, and one was left with life-threatening injuries.
The ANSA news agency reported four victims have been wounded while Sky TG24 put the number of wounded at two. A local man, he reportedly ran a year ago as a candidate in municipal elections for the anti-immigrant Northern League, which has since changed its name to the League to broaden its appeal.
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On January 31, Putin said the IOC's decision to ban Russia from the Olympics amounted to an "outside attack" on Russian sports. Russian Federation has repeatedly denied state involvement in doping.
The attack comes a day after a Nigerian asylum-seeker and drug dealer was arrested in Macerata over the gruesome killing of an 18-year-old Italian woman whose dismembered body was discovered in suitcases earlier this week. People injured. Police operation under way.
"Whoever, like Salvini, exploits news events and tragedies for electoral purposes is among those responsible for the spiral of hatred and violence that we must stop as soon as possible", Grasso said.
Police have not said how many people were wounded in Saturday's shootings.
The mayor of Macerata, located about 200 km (125 miles) east of Rome, appealed to locals to remain indoors, according to Reuters. While the shooter was still active, police told residents to stay inside and ordered public transport halted.
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His tweet read, "Well done Rajasthan Congress!" The Congress drew a blank in Rajasthan in the 2014 Lok Sabha polls. Karan Singh Yadav of Congress , reportedly, won the Alwar Lok Sabha seat by 1.97 lakh votes.