Former Home Secretary David Blunkett has called for internet providers to block pornography, warning against a descent into "Sodom and Gomorrah".

Mr Blunkett backed an opt-in system of censorship, saying the Lib Dems had been wrong to reject it at their party conference last week.

Civilised society risked being undermined by "the most bestial activities", he warned.

He was speaking at a Demos fringe meeting at the Labour conference.