A Danish man has appeared in a closed court charged with subjecting an Auckland school girl to what police in New Zealand say were serious, constant and distressing online attacks.
The 24-year-old was arrested in his home city of Vejle, on the south east of Jutland Peninsula, after what police described as an intensive investigation.
It was a joint operation between local police in Denmark, the Danish National Cyber Crime Centre, and New Zealand's Police Cybercrime Unit.
The man's charges relate to online posting of private photos and hacking of private computers. Police in Denmark are not able to go into more detail because of the court process.
Superintendent Preben Hilliger was in charge of the investigation for South-East Jutland Police, which worked with New Zealand police officers for the first time.
"The case is very complex and we still need a lot of investigations before we can say anything more," he told Radio New Zealand.
"The material in the investigation - that leads to the decision about taking action against the man and making the arrest."
Police in New Zealand say the attacks were persistent and particularly distressing for the 15-year-old girl and her family.
Superintendent Hilliger said for legal reasons he was unable to say what penalties the man could face if he was convicted.
The girl and her family first approached the New Zealand internet safety group NetSafe earlier this year.
NetSafe said it had up to 10 complaints of online sexual exploitation a month and cybercrime of this sort was on the rise.
Executive director Martin Cocker said a few years ago they had no reports of this sort of incident and now they had several a month.
Operations manager Lee Chisholm said it made the decision to call in the police.
"We definitely could see that this was something that needed to involve the police and so we helped that happen. "It was very distressing for the young woman and her family, and quite serious."
NetSafe was no longer involved in helping the girl, and Ms Chisholm said she hoped she was still getting support. "Certainly it was quite a sustained attack on the young woman," she said. "Anyone in that situation needs support."
Detective Senior Sergeant Cliff Clark from the New Zealand Cybercrime Unit said the police were pleased for the girl and her family that an arrest had been made, which he said demonstrated the value of effective co-operation.
Superintent Preben Hilliger from the South East Jutland Police said this relationship would continue as officers continued to investigate the case. "We must say the co-operation with your agency has been very, very good," he said.
Assocation of Councillors's schools councilling spokesperson Srah Maindonald said this type of cybercrime could have a huge impact on students and affect their schooling.
She said people should be aware of, and concerned about the sexualisation of social media, and young people needed to be educated.