A detention center or a detention centre is any location used for detention. Specifically, it can mean:

A jail or prison, a facility in which inmates are forcibly confined and denied a variety of freedoms under the authority of the state as a form of punishment after being convicted of crimes
A structure for immigration detention
An internment camp
A youth detention center, a secure prison or jail for persons under the age of majority
https://en.wikipedia.org/wiki/Detention_center

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Note added at 11 мин (2018-08-14 20:52:03 GMT)
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For example:

The Metropolitan Detention Center, Brooklyn (MDC Brooklyn) is a United States federal administrative detention facility in Brooklyn, New York City which holds male and female prisoners of all security levels. It is operated by the Federal Bureau of Prisons, a division of the United States Department of Justice.

Most prisoners held at MDC Brooklyn have pending cases in the United States District Court for the Eastern District of New York. MDC Brooklyn also holds prisoners serving brief sentences.[1]
https://en.wikipedia.org/wiki/Metropolitan_Detention_Center,...