Crimes stemming from people meeting through online personal sites are on the increase in Japan.
There were three times as many in the first half of the year compared with all of 2000, according to the National Police Agency.
Most of the crimes involved child prostitution or porn, though they also included killings and rapes.
Nearly all involved the use of mobile phones which led to 85 per cent of the 302 'lonely hearts' crimes recorded from January to the end of June.
Of the 283 victims during that period, 218 were minors and 90 per cent were female.
The Mainichi Daily Newsreports violations of the law banning child pornography and child prostitution accounted for 133 cases, and offences against guidelines aimed at protecting youths made up 59 cases.
Twenty rapes were recorded and there were 14 robbery victims and five murders.
AP