UPDATE 1-Chile must prosecute police, army for violence against protesters - UN
* UN rights office reports serious violations by security forces
* Says 345 people suffered eye injuries from anti-riot shotguns
* Documented dozens of cases of torture and sexual violence
* Protest death toll of 26 includes at least 4 unlawful deaths (Adds details, quotes)
GENEVA, Dec 13 (Reuters) - Chilean police and soldiers used excessive or unnecessary force to quell recent demonstrations, committing serious human rights violations including unlawful killings and torture that should be prosecuted, the United Nations said on Friday.
The U.N. human rights office said in a report it had documented an "alarmingly high number" of 345 people suffering eye injuries after being hit by lead pellets fired from anti-riot shotguns by security forces.
Twenty-six people were killed in the protests that began in October over a rise in metro fares but quickly spiraled out of control.
"We have found that the overall management of assemblies by the police was carried out in a fundamentally repressive manner," U.N. mission leader Imma Guerras-Delgado told a Geneva news briefing.
"Human rights violations documented ... include the excessive or unnecessary use of force that led to unlawful killings and injuries, arbitary detentions, and torture and ill-treatment including sexual violence," she said.
There was no immediate reaction to the report by the office of U.N. rights boss Michelle Bachelet, a former president of Chile, from the government of President Sebastian Pinera, which the U.N. team said had cooperated with its investigation.
During its Oct 30-Nov 22 mission, the U.N. team documented 113 specific cases of torture and ill-treatment - mainly through "severe beatings" - and 24 cases of sexual violence against women, men and adolescents by members of the police and army.
It documented four unlawful deaths "involving state agents," including two without there having been any apparent risk to the lives of the military personnel, which could amount to an extrajudicial execution, Guerras-Delgado said.
Some 1,615 people remain in pre-trial detention among 28,000 detained since mid-October, she said.
The U.N. team also observed numerous attacks against the security forces and their premises as well as looting and destruction of private and public property, she said.
"We continue to receive allegations of violations by police forces," Guerras-Delgado said. "We recommend the immediate end of the indiscriminate use of anti-riot shotguns to control demonstrations." (Reporting by Stephanie Nebehay; editing by John Stonestreet and Angus MacSwan)
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