But the report was bluntly rejected by Italy's chief of police, who completely denied the use of violent methods in the force's handling of migrants.
"The European Union's pressure on Italy to 'get tough' on refugees and migrants has led to unlawful expulsions and ill-treatment which in some cases may amount to torture," the London-based rights watchdog said in a report.
The EU-sponsored "hotspot approach" for processing people -- which requires Italy to fingerprint new arrivals so they can be prevented from claiming asylum elsewhere -- has even seen minors abused, according to testimony from over 170 migrants.
The allegations of violence were swiftly denied by chief of police Franco Gabrielli.
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"I categorically deny that violent methods were used against migrants, either during their identification process or repatriation," he said in a statement.
Last year, Europe saw an influx of more than one million migrants and asylum seekers fleeing war and poverty in its worst such crisis since World War II.
"In their determination to reduce the onward movement of refugees and migrants to other member states, EU leaders have driven the Italian authorities to the limits -- and beyond -- of what is legal," said Matteo de Bellis, Amnesty International's Italy Researcher.
Of the 24 reports of ill-treatment Amnesty gathered, 16 involved beatings.
In several cases, people also said they had been given electric shocks with stun batons, including a 16-year-old boy from Sudan.