The number of tip-offs received by an Internet hot line about illegal information on websites soared 75.3 per cent in the first half of this year from a year before to hit a record half-year high of over 18,000, the National Police Agency has said.

During the January-June period, the Internet Hotline Center received 18,542 reports of illegal information posted on websites, such as child pornography and advertising of banned drugs, the highest number since it started operations in 2006, the NPA said yesterday.

The center also received 5,441 reports about harmful information on the Internet, including offers to commit murders for money and soliciting suicides, marking a 53.9 per cent jump, according to the NPA.

The Tokyo-based center asked operators of the websites involved to delete illegal information in 9,602 cases. Of them, illegal information in 2,014 cases, including 239 containing child porn images, had yet to be deleted after more than two months as the center's requests are nonbinding.

Based on reports from the center, police charged people involved in 226 cases, up 174 from a year earlier, including 117 cases pertaining to child porn.

It is feared that indecent images of children on the Internet, if posted for a long period of time, may inflict much more serious damage on the children through repeated duplication.

The government has been preparing to have Internet service providers block access to child pornography based on tip-offs to the center and other reports.

The center has been operated by the Internet Association Japan, a group for Net-related firms, since June 2006 on behalf of the NPA.