Police posed as a 13-year-old girl to capture an Auckland man who had been grooming young teens and pressuring them into meeting for sex.
Through text messages they arranged a meeting with Andy Samoa, 38, at a North Shore park for sex.
He thought he was meeting the teenager - but police were waiting.
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Now police are urging parents to speak to their children and teenagers about dangers of online predators after the man was jailed for offending against young people he groomed on social media sites.
Samoa was jailed for four years and three months last week after he was convicted on 14 charges of sexual abuse and grooming.
The Auckland man must serve half of that sentence before he is eligible for parole.
The Herald was at Samoa's sentencing in the North Shore District Court before Judge Claire Ryan.
He had earlier pleaded guilty to a raft of charges including sexual connection with a person under 16, indecently exposing a person under 16 to explicit material, arranging to meet a young person with the purpose of sexual connection and offering to supply cannabis.
Over a period of 15 months Samoa targeted three young people - a 13-year-old girl and two 14-year-old boys - after meeting them on social media sites.
He used applications including Whisper and Viber but later texted the victims.
Samoa said he went online to find people to have sex with because his relationship had broken up, he was "lonely" and had a high sex drive.
He initially met other adults but moved on to the teenagers.
He was aware of their ages and lied to them, saying he was either 19 or 20, to gain their trust and friendship.
Samoa then went about trying to get the teenagers to meet him for sexual encounters.
He sent explicit text messages and photographs to them and offered them cash, cannabis and cigarettes.
Only one of the teenagers met Samoa - sneaking out at night to be picked up and driven to Hillsborough where he was sexually abused.
Samoa was arrested after the other teenage boy told his parents about the messages and they went to police.
Officers then posed as a young person and responded to messages from Samoa, agreeing to meet him in a park for sex.
When he arrived for the meeting, police pounced.
Judge Ryan said Samoa's offending had a "high degree of premeditation, planning and grooming".
She said all three victims were vulnerable - not just because of their age - and Samoa preyed on them for his own sexual gratification.
Despite his early guilty plea, he had shown little empathy or remorse.
"You knew they were vulnerable and you took advantage of that," she said.
"This was serious offending against 13- and 14-year-olds and you haven't just done it once or five times or eight times - you've done it 16 times.
"Your remorse, in my view, is extremely limited - largely for the predicament you are in.
"You seem to lack insight into the severity of your offending, trying to excuse it."
Detective Inspector John Sutton said Samoa's arrest was significant.
"He was a predator, preying on the naivety of young people and taking advantage," he said.
Sutton said police initially received two separate complaints about a man contacting young people online.
Officers ascertained the same person was behind the contact but they did not know his real identity.
They managed to link the messaging back to Samoa and set up a meeting with him in a North Shore park, posing as the teenage girl.
When he arrived he sent the "girl" a message confirming he was there and described his car.
Police then moved in and arrested him.
"As the investigation went on further, information came to hand that there was a third victim who a number of charges related to," Sutton said.
"He was using all the social media apps to make contact with these young people, grooming them to get their trust and persuading them to have sex with him."
Sutton said the case showed how important it was for parent and guardians to communicated with their children about being safe online.
"We've got to make sure our young people are aware and prepared to talk to their parents," he said.
"If you're concerned about a person's behaviour online, ring the police and tell them what's happening.
"To the people who are out there doing this, or thinking about doing it - we will look for you and we will try and catch you."
Avoid predators - help your kids stay safe online
Some things you can do to help your children stay safe online include:
• install software on your computer that either blocks restricted content so your children cannot access certain sites, or monitors activity so you can review online behaviour
• know who your children are contacting online. If they are not your children's actual friends then question their cyber friendship
• know which social networking sites your child is on and what they are posting
• check that your children understand the dangers of posting personal information on social networking sites
• do not allow your children to use the computer in private areas of your home
• if you or your child becomes suspicious about a person online, stop contact immediately.
If you are concerned about a young person or someone's online behaviour - contact your local police station to speak to an officer.
If you or someone you know is in danger - call 111 immediately.
For more information and safety tips visit:
Police http://www.police.govt.nz/advice/email-and-internet-safety/online-child-safety
Netsafe https://www.netsafe.org.nz/online-safety-for-parents/