One in five British children under the age of 17 who have access to the internet are looking at pornography.

Once they reach a sex website, they stay there for an average of 28 minutes.

More than a quarter of users in this age group have visited gambling sites, where they stay for an average 11.3 minutes.

According to research from the internet monitoring company, NetValue, the number of UK under-17s who are online has grown by 44% in the past six months.

Britain has more internet users in this age group than any other European country included in the study.

More than one in nine has internet access at home. On average, children go online for five hours and 48 minutes each month. And 35.8% of children download music and watch video clips.

According to the study, the UK websites to attract the highest number of young visitors are upcomingmovie.com, uproar.com, swapitshop.com, cartoonnetwork.com and cheatplanet.com.