Assistant Chief Constable Mark Hamilton is leading the operation into sexual abuse against 22 young people, between 13 and 18, who were in care.
He confirmed that 18 children identified as potential victims went missing from care more than 400 times in a year and a half.
More than 30 arrests have been made in the case and as many as 50 suspects have been identified so far.
ACC Hamilton revealed that many of the men have criminal backgrounds and range in age from teenagers to 60 year olds.
Most of the people the police believe are involved in the abuse are in their early 20s.
We have to break through the walls of intimidation around these offences.
ACC Mark Hamilton
"There is no actual statutory crime of child sexual exploitation but the offences that are committed under that umbrella term are grooming, rape, unlawful carnal knowledge, indecent assault, sexual contact with a child, physical assault, intimidation, threats," he continued.
"These are a range of offences, (also including) supplying of drugs, supplying of alcohol."
He said the men were supplying anything from affection, drugs and gifts to try and meet a need that a child feels is not being met elsewhere in their life.
"They exploit that need, that then turns to sexual contact and can expand from there.
"This is about preying on vulnerability and our model for this is about starting with vulnerability."
ACC Hamilton said they have received information that some children were passed between parties in taxis and supplied with drink and drugs and then abused.
"In many cases a child might be lured into this activity on a one-to-one basis and at that time mightn't understand at all that they are being made a victim, but it can spiral out of control for them when more perpetrators enter the scene.
"They are then in a terrible dark place, threats then ensue and it's hard to get out of there."
The Assistant Chief Constable said that the alleged victims were all in care but that this was not the main issue - he said the focus should be on the predators who are targeting these vulnerable young people for sex.
"We need to be careful that we don't label it too quickly in terms of categories of victim or categories of offender because it then the focus or attention is too narrow," he commented.
He continued: "One of the things we're saying to victims is don't be afraid to come to us, to talk to us about what has happened.
"Don't be afraid if people say you have contributed to this or something, because they haven't.
He said some cases that had been reported were investigated and arrests made.
"What we are learning in the police is that we haven't been making sufficient and quick enough connections between victims and offenders," ACC Hamilton said.
"It's not necessarily that they have covered all their tracks, they have been arrested, but we need to be better about pulling together all the information, all the evidence."
But he denied that the police had failed these children.
"The system has to improve. I'm not saying we've failed children, I think people have been working exceptionally hard but any system that doesn't recognise that it must get better to serve the people who we are sworn to serve would be failing.
"I think we have really busy child abuse investigators working all the time, but many of the children have complex needs and have been difficult to reach and difficult to establish evidence from them to bring to court.
"What we're accepting as a criminal justice agency, we're all accepting, is that we need to make better efforts with the children, understand better ways to get the evidence, make early interventions to protect them to give them time if necessary."
The senior police officer said the PSNI and other jurisdictions needed to work more closely with the prosecution service and other partners to try and get the better outcome for victims.
NSPCC telephone: 0800 389 1701
"There is not as much knowledge generally about this type of offending there would be about other more recognised forms of child sexual abuse and so there is a challenge for us all to gather more knowledge about them which actually helps us bring justice."