Israel has vowed to step up pressure on Hamas, who it has blamed for the disappearance of three Israeli teenagers.
Army spokesman Lt Col Peter Lerner said militants "will not feel safe" until the teenagers, including a 16-year-old American, return home.
The two 16-year-olds and a third, 19-year-old man disappeared on Thursday night after their left a Jewish settlement bloc where they were students.
Since then the army has carried out house-to-house searches, round-ups and interrogations in the nearby Palestinian city of Hebron and outlying villages.
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