"The total number of children detained is 103,000"he declared Manfred Nowak, lead author of United Nations Global Survey on Children Deprived of Liberty.
Nowak described as "prudent" this estimate, based on official figures as well as "very reliable" complementary sources.
The specialist said that the number of 103,000 children detained in the United States includes unaccompanied minors, those who went with their relatives and those who were separated of his parents before the arrest.
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Worldwide, at least 330,000 minors are detained in 80 countries for reasons linked to migration, according to this study.
"Detention of minors related to migration should never be applied … in the interest of the child. There are always other options "Nowak told reporters in Geneva.
The study especially examines violations of the Convention on the Human Rights of the child, which stipulates that the detention of children should only be used "as a measure of last resort and of the shortest possible duration".
U.S it is the only member country of the United Nations that did not ratify the Convention, which entered into force in 1990.
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But Nowak stressed that that does not exonerate the administration of president Donald Trump of the responsibility of their acts in the matter of detention of migrant children on their border with Mexico.
"Separate children from their parents, as did the Trump administration on the border with Mexico, It is an inhuman treatment at the same time for the parents and for the child"he stressed.
He stated that the US administration did not respond to a questionnaire sent to member states to prepare a study on the subject.