Tareq Abu Khdeir, speaking via a representative from the US consulate in Jerusalem who was allowed to visit him in the police station, sent a message to his parents: "I am holding up OK."
The fifteen year old, who is an American citizen and attends high school in Florida, is alleged to have been badly beaten by Israeli security forces during violent clashes in East Jerusalem on Thursday.
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Theresa May has launched her bid to become the next leader of the Conservative Party.
The government is set to announce that David Cameron's successor will make the decision on whether to expand Heathrow or Gatwick.
Michael Gove is to stand for the Conservative Party leadership, saying he does not believe Boris Johnson can "provide the leadership".