Special needs teacher Jane Longhurst was strangled and raped

Graham Coutts, who was found guilty last month of murdering the Brighton teacher, had a history of logging into necrophilia websites.

The Longhurst family met David Blunkett to call for the sites to be blocked.

After the meeting, Jane's sister Sue Barnett, told the BBC the family felt it would be a long, drawn-out process.

If there's a political will to do it, the means are there by which these sites can be removed John Giacobbi, web expert

She said: "My sister was strangled and raped.

"God forbid something like this happens to anybody else."

Ms Barnett said: "I think the government needs to become more savvy with this - I think they need to be educated."

She said only now had the government started to engage with internet service providers to look at controlling their content.

Internet expert John Giacobbi has pinpointed some of the pages the 35-year-old Hove musician Coutts viewed before murdering the Brighton teacher.

His company Web Sheriff, based in London and Marlborough, has already disabled one of the violent pornographic website's billing pages, so no new users can pay to view the images.

He said: "It would perhaps take 24 to 48 hours, but if there's a political will to do it, the means are there by which these sites can be removed."

Mark Stevens, the lawyer who founded the Internet Watch Foundation, said: "The only area where we have universal acceptance that depiction is as bad as the act itself, is paedophilia.

"Is there a broader category of offence - for example extreme non-consensual violence?

"Is it time we actually draw our horns in and say reasonable, decent people do not need to see this?"

This week, Britain and America agreed to set up a group to investigate ways of stopping violent internet sex sites in a meeting between Home Secretary David Blunkett and US Deputy Attorney General Jim Comey.