Last Updated Jul 6, 2014 7:00 PM EDT
JERUSALEM - Israeli authorities on Sunday announced the arrests of several Jewish suspects in the death of a Palestinian teenager who was abducted and burned alive last week, marking a major breakthrough in a case that has sparked violent protests in Arab areas of Jerusalem and northern Israel.
In a joint statement, Israeli police and the Shin Bet security agency said the suspects were arrested early Sunday. They remained in custody and were being interrogated by Shin Bet.
While the statement did not say how many suspects were in custody, an official speaking on condition of anonymity because the investigation was ongoing said they numbered six in total.
The announcement shed new light on a case that has gripped the country's attention since Mohammed Abu Khdeir, 16, was abducted outside his home in east Jerusalem early Wednesday and his charred remains were found in a Jerusalem forest shortly afterward. Palestinians immediately accused Jewish extremists of killing Abu Khdeir to avenge the earlier kidnapping and killings of three Israeli teens.
Police had investigated various motives for Abu Khdeir's death, including criminal or personal motives. But officials said Sunday they believed the killers acted on "nationalistic" grounds.
The official described the suspects as young males, including several minors, and said they came from Jerusalem, the nearby city of Beit Shemesh and Adam, a West Bank settlement near Jerusalem.
He said police had located a car used by the suspects, and that security camera footage allegedly showing parts of the abduction in recent days did not help police. During the investigation, however, police learned of an attempting kidnapping the previous day of a young child in the same east Jerusalem neighborhood and concluded the incidents were linked.
News of Abu Khdeir's death triggered violent protests in the east Jerusalem neighborhood where he lived, as angry crowds destroyed light-rail train stations, clashed with police and littered roads with stones and debris. The unrest spread to Arab areas of northern Israel over the weekend.
In east Jerusalem, home to the most violent protests over the teen's death, Abu Khdeir's family said news of the arrests brought them little joy.
"I don't have any peace in my heart, even if they captured who they say killed my son," said his mother, Suha. "They're only going to ask them questions and then release them. What's the point?
"They need to treat them the way they treat us. They need to demolish their homes and round them up, the way they do it to our children," she added.
His father, Hussein, said the family still had not been officially informed of any arrests. "Even if they rounded up all of Israel, they will not bring my son back," he said.
Palestinians have alleged that Abu Khdeir was killed by Jewish extremists to avenge the killings of the three Israeli teenagers, who were abducted in the West Bank on June 12. Their bodies were found last week, and Abu Khdeir was killed just hours after their funeral.
Adding to the tensions, Palestinian militants in the Gaza Strip have stepped up rocket attacks on southern Israel, drawing Israeli airstrikes in retaliation. At midday Sunday, militants fired eight more rockets into Israel, the military said. Overnight, Israel had carried out airstrikes on 10 sites in Gaza.
Prime Minister Benjamin Netanyahu said Sunday that Israel would act calmly and responsibly in the face of rising Israeli-Palestinian hostilities.
"Experience proves that in moments like these, one must act calmly and responsibly, not hysterically and hastily," Netanyahu said at the opening of his weekly Cabinet meeting.
His statement came after weekend clashes between Israeli police and demonstrators in Jerusalem and Arab towns in northern Israel following Abu Khdeir's death. On Sunday, Tariq Abu Khdeir, a 15-year-old Palestinian-American who was badly injured in clashes with Israeli police, was sentenced to nine days of home detention.
His parents say Tariq Abu Khdeir, who goes to school in Florida, was beaten Thursday by Israeli police during clashes over the killing of Mohammed Abu Khdeir. The two youths were cousins.
His face covered in bruises, Tariq told CBS News that he was trying to run away from the clashes when Israeli security forces grabbed him.
"They punched me, they kicked me, they kicked me in my face. They made sure I wasn't able to see anything. I wasn't even breathing," he said.
"They didn't stop. They were carrying me and still kicking me and punching me. Even when I was unconscious," he said.
He said he was haunted by thoughts of his murdered cousin.
"I can still remember his voice in my head," Tariq said. It's like he's still here. Just that like nobody can see him."