A series of disturbances that took place at the Children's Detention Centre in Oberstown last night and this morning are being investigated by gardaí.
Staff were threatened and four inmates are understood to have taken over one of the units causing extensive damage.

One inmate also set fire to a mattress in a separate part of the centre last night while earlier another juvenile was taken to hospital after a suspected overdose and had to be restrained after he tried to escape.

It is believed four units at Oberstown have now been damaged or closed due to the disturbances over the past three weeks.

Oberstown declined to comment on the incidents, which it described as "operational matters".

However, Campus Director Pat Bergin said in a statement today that challenging behaviour was a factor in such an environment but with the co-operation of staff, young people are kept safe and normal routines reinstated.

Staff at the centre, however, have already expressed concern for their health and safety and have taken industrial action.

Earlier this week Minister for Children Katherine Zappone announced a review of operations at Oberstown following other serious incidents last month, including a fire at one of the buildings at the campus and a rooftop protest during which a staff member was injured.