JERUSALEM — A teenager who Palestinians say was killed by Israeli extremists in a revenge attack was burned to death, an autopsy showed Saturday. Palestinian Attorney General Abdelghani al-Owaiwi said initial results show that 16-year-old Mohammed Abu Khdeir suffered burns on "90 percent of his body." Abu Khdeir's charred body was found in a forest after he was seized near his home. Palestinians immediately accused Israeli extremists of killing him to avenge the deaths of three Israeli teens who had been abducted and killed in the West Bank.

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Riots erupted in east Jerusalem Friday as thousands of Palestinians massed for the boy's burial. The violence spread to Arab towns in northern Israel early Saturday, with protesters burning tires and throwing rocks at passing cars at police, who responded with tear gas and stun grenades, Israeli police spokeswoman Luba Samri said. The chaos began after three Israeli teenagers were abducted in the West Bank on June 12, sparking a manhunt that ended with the discovery of their bodies earlier this week.

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—The Associated Press