Some two-thirds of Dutch children have had an unpleasant experience on the internet, according to a new survey of teenagers aged 12 to 16.

The research was carried out among 410 teenagers and 232 parents by Digibewust, an organisation that encourages safe use of the internet.

Of those who took part, 46% said they had been approached by someone unknown online. These experiences include cyber-bullying and grooming – the process by which an adult poses as a peer to lure a child into sexual activity.

Other experiences were having an account hacked (21%), bullying on social media such as Facebook (19%) and being conned (14%).

Girls in particular face the risk of having saucy photographs taken by their boyfriends released online, the researchers said.