A group of unaccompanied child asylum seekers have been transferred from Nauru to Brisbane amid concerns about their mental health and fears they may try to self harm.

Fairfax Media understands the medical evacuation, which began on Friday has occurred in part because the Nauruan government has expressed safety concerns about the children.

Further, it is understood that one of the children being medically evacuated is a teenage girl who was only sent to Nauru three days ago. Fairfax Media has been told by well-placed sources the girl had attempted suicide on Christmas Island in recent weeks and had also been self harming but that did not prevent her deportation to Nauru.

A spokesman for Immigration Minister Scott Morrison said in a statement: "Any health transfers occur in accordance with standing policies.

"The Government's policy is that there are no exceptions to offshore processing.