Israeli Prime Minister Benjamin Netanyahu announced on Monday evening the discovery of the three bodies in a field in the southern West Bank.
“This evening, we found three bodies and all the signs indicate that they are the bodies of our three kidnapped youngsters,” Netanyahu told ministers at the start of an emergency session of his security cabinet.
“They were kidnapped and murdered in cold blood by human animals,” he said.
“Hamas is responsible and Hamas will pay.”
Hamas, which had denied any involvement in the abduction of the teenage boys, issued a warning in return to the Israelis.
“If the occupiers carry out an escalation or a war, they will open the gates of hell on themselves,” said Hamas spokesman Sami Abu Zuhri.
The discovery of the boys’ bodies, one 19-year-old and two aged 16, came 17 days after they disappeared, triggering a huge manhunt during which five Palestinians were killed and more than 400 arrested.
Two Hebron Hamas men named by Israel as prime suspects, Marwan Qawasmeh and Amer Abu Eishe — remain at large but Palestinian witnesses said troops blew up their homes early on Tuesday.
The Israeli roundup, mainly of people linked to Hamas, brought a wave of rocket attacks against southern Israel by militants in the Gaza Strip, answered in turn by Israeli air strikes.
The latest round began around 1am on Tuesday with a rocket slamming into open ground in the Negev desert region. An army statement said nobody was hurt.
Shortly afterwards the Palestinian interior ministry reported around 30 Israeli air strikes on deserted militant training sites across Gaza but there were no immediate reports of casualties.
In the northern West Bank, Israeli troops shot dead a young Palestinian early Tuesday during a raid into the Jenin refugee camp, Palestinian security and medical officials said.
They named the dead youth as Yusuf Abu Zagher (18) and said the incident appeared unrelated to Israeli operations in the southern part of the territory.
The Israeli military had no immediate comment.