Four in 10 Dutch 12 to 24-year-olds have had online sexual advances from a stranger, according to research for television programme EenVandaag.

The approaches were mainly in the form of sexually-tinged comments and suggestions but almost 20% said they had been sent provocative photographs or videos.

The research shows that sending sexually-charged photographs and messages is becoming increasingly accepted by Dutch teenagers and at a younger age, EenVandaag says.

Three-quarters were under the age of 18 when they received the approaches and only half the teenagers immediately stopped all contact, the research shows.

One in seven secondary school pupils say they have sent a nude or semi-nude photograph of themselves using Snapchat or other social media and seven in 10 are aware of instances in which the photograph has ended up in general circulation.

The research was carried out online using a panel of over 1,800 12 to 24-year-olds from all over the country and is representative for age, sex and location, EenVandaag says.

One-quarter of boys and 13% of girls also said they would have no problem taking their clothes off in front of a webcam, and one in seven of the youngsters polled claimed to have done so.