The keynote speaker at the event, at Otago Boys' High School on Tuesday night, Electronic Crime Laboratory forensic analyst Matt Taylor, explained to parents the risks by using as examples cases he had worked on. About 150 people attended the event.
The cases he brought up, which were all from the South Island, included one in which a man used the internet to convince teenage boys to commit sexual favours, at times posing as a pretty woman.
Another case involved a man in his late 50s who posed as a 21-year-old man and built up a relationship by text, lasting three years, with a 12-year-old girl.
The man eventually convinced the girl to send him sexually explicit pictures via text. Mr Taylor, who works at the Dunedin police station, said all teenagers were at risk from either sexual predators or bullying online, but there were things parents could do to stop their children from becoming victims.
Parents should ''take control'' of when children had access to the internet and mobile devices.
This meant having a mobile phone curfew and not allowing them to use computers in their bedrooms.
''You don't want the public in their bedroom,'' he saidParents should also start an ongoing discussion with teenagers about the risks they faced online and become friends with them on Facebook so they could keep an eye on what they were doing.
The event was supported by the Otago Secondary Principals' Association, police and the Southern District Health Board.
