A record high number of children were abused after contact via social media last year, with the vast majority becoming victims of underage sex or child pornography.

There were 1,421 recorded cases of children aged 17 or younger who fell victim to crime via social networking services, or 128 more than a year earlier, the National Police Agency reported Thursday.

That's the highest figure since 2008 when the NPA started a tally, the agency said.