JERUSALEM — Israeli Prime Minister Benjamin Netanyahu said Sunday that the kidnappers of three Israeli teenagers missing since Thursday in the West Bank were members of the militant Islamist group Hamas.
Netanyahu's remarks followed an Israeli security sweep overnight in which about 80 Palestinians were arrested across the West Bank, the army said.
Most of those detained were Hamas members, including prominent political figures, legislators and former Cabinet ministers affiliated with the group, Palestinians reported.
"Hamas terrorists carried out Thursday's kidnapping," Netanyahu said. "We know that for a fact."
In later remarks, Netanyahu seemed to hint at possible retaliation, saying: "This event will have consequences, and we are already discussing them."
U.S. officials were less certain in their pronouncements, but also aimed suspicion at Hamas.
"We are still seeking details on the parties responsible for this despicable terrorist act, although many indications point to Hamas' involvement," Secretary of State John Kerry said in a written statement. "As we gather this information, we reiterate our position that Hamas is a terrorist organization known for its attacks on innocent civilians and which has used kidnapping in the past."
Kerry said the United States had encouraged "full cooperation between the Israeli and Palestinian security services" and that that cooperation was "ongoing."
One of the missing teens, Naftali Frenkel, 16, a yeshiva student at the settlement of Gush Etzion, also holds U.S. citizenship. The others have been identified as Eyal Yifrah, 19, a student at a yeshiva in the Jewish settlement enclave in Hebron; and Gilad Shaar, 16, who attends the same school as Frenkel.
Under a reconciliation deal reached by Hamas and the Fatah movement of Palestinian President Mahmoud Abbas, an interim government backed by both factions was formed this month. Israel suspended peace talks with the Palestinians and says it will not negotiate with the Hamas-backed government.
Hamas refuses to recognize Israel and is deemed a terrorist organization by Israel, the United States and the European Union.
Netanyahu, who has seized on the kidnapping to criticize Abbas' alliance with Hamas, did not disclose what evidence backs his assertion that the kidnappers belonged to the group.
Hamas declined to comment.