RAMALLAH, West Bank — An autopsy report states that an Arab teenager who Palestinians say was killed in a revenge attack was burned to death, officials said Saturday, while Palestinian militants fired two rockets toward a major southern city deeper into Israel than any other attack in the current round of violence.
The Israeli military said its ‘‘Iron Dome’’ defense system intercepted the rockets that were aimed at Beersheba. The military also said that at least 29 other rockets and mortar shells were fired from the Gaza Strip and said it had retaliated with airstrikes on militant sites in Gaza.
Clashes between Israeli police and Palestinian protesters spread Saturday from Jerusalem to Arab towns in northern Israel as hundreds of people took to the streets and threw rocks and fire bombs at officers who responded with tear gas and stun grenades.
The Israeli military said Palestinian militants have fired more than 150 rockets at southern Israel, and it has responded with airstrikes on more than 70 targets in Gaza.
Palestinian Attorney General Abdelghani al-Owaiwi said he received initial autopsy results from a Palestinian doctor who was present at the autopsy in Tel Aviv. He said it shows that 16-year-old Palestinian Mohammed Abu Khdeir, whose death has sparked large protests in his East Jerusalem neighborhood, suffered burns on ‘‘90 percent of his body.’’
‘‘The results show he was breathing while on fire and died from burns and their consequences,’’ Owaiwi said.
His account provided the first details of the preliminary findings to be made public. The Israeli Health Ministry could not be reached for comment.
The autopsy found evidence that Abu Khdeir had breathed in the flames as burns were found inside his body, in his lungs, bronchial tubes and his throat, Owaiwi said.
He also said the young man had suffered wounds on the right side of his head, apparently from impact with a rock or another hard object.
Abu Khdeir’s charred body was found in a forest Wednesday 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. Israeli police said an investigation is still underway and they have not yet determined who killed the boy or why.
Israeli leaders have widely condemned the killing of the Palestinian youth, and Prime Minister Benjamin Netanyahu vowed those responsible would be brought to justice.
Palestinians took to the streets in protests after news of the boy’s death on Wednesday and clashed with police in East Jerusalem. Riots erupted in East Jerusalem on Friday as thousands of Palestinians massed for the boy’s burial.
The violence spread to Arab towns in northern Israel early Saturday, with protesters throwing rocks at passing cars, burning tires, and lobbing rocks and firebombs at police, who responded with tear gas and stun grenades, Israeli police spokeswoman Luba Samri said.
Near the town of Qalansawe, protesters also pulled over a car driven by an Israeli Jew, pulled him out, and set the vehicle on fire, Samri said. The driver was not injured. Several other Israeli cars were also torched, she said. Dozens of people were arrested.
Protests subsided by noon Saturday but resumed in the evening with violent demonstrations in several Arab towns in the north of the country, police said.
Israel’s public security minister, Yitzhak Aharonovitch, visited areas of friction and said police would display ‘‘zero tolerance’’ toward those ‘‘who take the law into their own hands and harm innocent people.’’
Israeli Arabs, unlike Palestinians in the West Bank and Gaza Strip, hold citizenship rights. But they often face discrimination and mostly identify with the Palestinians. Even so, violent riots like these are rare.
The chaos began after three Israeli teenagers, one of whom was a US citizen, were abducted in the West Bank on June 12, sparking a huge manhunt that ended with the discovery of their bodies last week.