Appeal to parents after 'most depraved' catfish case

"Paedophiles will go wherever children are, in the real world and in the online world.

"And we'd just implore everybody who cares about children - the mums and dads, and grannies and grandads - please speak to the young people in your life.

"And please warn them of the dangers of going online and speaking to strangers because you just don't know what the consequences could be."

Prosecutors in Northern Ireland who worked on the case of Alexander McCartney described the case as the largest, most complex and depraved investigation into sexual offences they had ever worked on.

It is highly likely that more than 70 victims were targeted by McCartney but police have not been able to identify them - so the harm he caused is unquantifiable.

Chief prosecutor was Catherine Kierans, acting head of the serious crime unit in Northern Ireland's Public Prosecution Service.

She said: "This is probably the most depraved case we've ever dealt with in the serious crime unit.

"But what kept us going, we were totally inspired by the bravery of all the little girls involved in this case.

"As they were identified, many of them gave evidence and they were so brave, they were ready to face down McCartney if need be. Obviously we were going to support them through that. Now luckily he did plead guilty and that didn't have to happen but that is what kept us going, the bravery of the little victims."

Ms Kierans spoke to our Northern Editor Vincent Kearney about the case, advising parents and grandparents to do all they can to protect children in their families.