UPDATED: The youths removed themselves from the roof of the centre "of their own volition" about 10.45pm, police confirmed.
EARLIER: Several youths are on the roof of the Ashley Detention Centre in the state's North.
Tasmania Police said the youths are refusing to come down.
No one has been injured.
The incident was continuing as of 9pm Friday, after being first made public about 5.25pm.
Tasmania Police say further details will be released when they're available.
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