Israeli soldiers man a checkpoint in the West Bank town of Hebron on June 15, 2014, as Israel broadened the search for three teenagers believed kidnapped by militants and imposed a tight closure of the town. (MENAHEM KAHANA/AFP/Getty Images)

A massive search is underway for three Israeli teenagers kidnapped Thursday in the West Bank, with Israeli forces detaining nearly 150 people—many of them members of Hamas and some of them senior Hamas officials—in door-to-door searches of six Palestinian towns. A 20-year-old Palestinian was killed by gunfire after protestors threw stones at the Israeli troops.

Israeli Prime Minister Benjamin Netanyahu publicly blamed Hamas for the kidnapping of the three boys—16-year-old Gil-Ad Shaer and Naftali Frankel and 19-year-old Eyal Yifrah—who disappeared while hitchhiking from their yeshiva in Gush Etzion. Frankel has dual U.S.-Israeli citizenship, which, according to the New York Times, has meant Washington “has been deeply engaged in the crisis.”

The military initiative carried out in the wake of the boys’ disappearance, the Times reports, was the largest in the West Bank in years:

Israel also carried out six airstrikes in the Gaza Strip overnight in response to rocket fire, wounding a 15-year-old girl and a 27-year-old woman. It closed commercial and pedestrian crossings into Gaza with exceptions only for fuel deliveries and humanitarian emergencies, and canceled family visits to Palestinians in Israeli jails this week. On Sunday night, four rockets were fired from Gaza into southern Israel.

Hamas has not claimed responsibility for the kidnapping. Palestinian President Mahmoud Abbas condemned the incident in a rare phone conversation with Netanyahu—who reportedly told him, “I expect you to help in returning the youths and capturing the kidnappers”—and in a public statement. Palestinian security chiefs have reportedly aided the investigation.

On Sunday it was reported that Israeli police received a call from one of the boys around 10:30 p.m. on Thursday. He whispered, “We have been kidnapped,” before the phone call cut out—but police dismissed it as a prank until one of the boy’s mothers reported him missing later that night.

A service at the Western Wall led by Chief Rabbi David Lau last night drew more than 25,000 people praying for the boys’ safe return.

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