Police in Northern Ireland have begun an investigation into the suspected sexual abuse of children who were in the care system.
Details of individual cases have not been released, but in a statement a police spokesperson said that officers have become "increasingly concerned about the issue of child sexual exploitation following an internal review.
Health Minister Edwin Poots said the abuse was on a scale comparable to that in the recent Rochdale and Oxford cases.
"As part of this review, we have identified a group of 22 young people who may be at risk from child sexual exploitation and are seeking to identify those who may have committed crimes against them," said police.
Police believe that the vulnerable children may have been targeted by a group of older men, with the abuse taking place away from care homes. The children's charity Barnados and social services are helping with the investigation.
Victims or anyone with information relevant to the investigation have been asked to contact police.
The operation is to be discussed in Stormont on Monday at a joint meeting of the justice and health committees.
Poots and Justice Minister David Ford are due to attend the meeting, which was called by justice committee chairman Paul Givan.
Mr Givan described the reports of child sexual exploitation as "gravely disturbing".
"The horrors of these crimes leave us only to pray for the victims and work towards ensuring the perpetrators are brought to justice.
"The public will be deeply concerned at this development and need to hear from the relevant authorities as to what has happened."
He said said the meeting would provide "an opportunity to probe what actions are being taken to investigate and bring to justice those responsible".
In April, the NSPCC described the level of child abuse in Northern Ireland as "disturbing".
Earlier this year a group of nine men in Rochdale and Oldham were accused of grooming and sexually exploiting girls as young as 13. In the same month, a gang of seven from Oxford was convicted of sexually abusing vulnerable girls "to the point of torture."
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