* Senior Conservative accused of child sex abuse in 1970s
* Claims have stoked fears of paedophile ring
* Government warns against "trial by Twitter"
By Guy Faulconbridge and Matt Falloon
LONDON, Nov 8 (Reuters) - Speculation about the identity of a senior Conservative party member accused of child sex abuse could descend into a "witch-hunt" of homosexuals, British Prime Minister David Cameron said on Thursday.
Cameron ordered an investigation this week after a child abuse victim said a prominent member of the prime minister's party had abused him during the 1970s, prompting Internet speculation over who the politician might be.
The claims, which follow the unmasking of late BBC star presenter Jimmy Savile as one of Britain's most prolific sex offenders, have stoked concern that a powerful paedophile ring may have operated in Britain in the 1970s and 1980s.
"I have heard all sorts of names bandied around and what then tends to happen is of course that everyone then sits around and speculates about people, some of whom are alive, some of whom are dead," Cameron said during an ITV television interview.
"It is very important that anyone who has got any information about any paedophile no matter how high up in the country go to the police," he said.
Britain's interior minister warned lawmakers this week that if they named suspected child abusers in parliament they risked jeopardising future trials.
MPs benefit from "parliamentary privilege" - meaning they can speak inside parliament freely without fear of legal action on sensitive issues that might otherwise attract lawsuits.
"TRIAL BY TWITTER"
The allegations could prove damaging to Cameron's party - which rules in an uneasy coalition with centrists - and tarnish the image of the era of Margaret Thatcher, prime minister from 1979 to 1990.
When the ITV interviewer passed Cameron a piece of paper with the names of people identified on the Internet as being alleged child abusers, Cameron said: "There is a danger, if we are not careful, that this could turn into a sort of witch-hunt, particularly against people who are gay."
"I am worried about the sort of thing you are doing right now - giving me a list of names you have taken off the Internet," Cameron said.
Steven Messham, one of hundreds of victims of sexual abuse at children's care homes in Wales over two decades, said in a TV programme last week that he had been sexually abused by a prominent Conservative political figure.
However, the BBC reporter said he could not publicly identify the accused person as there was "simply not enough evidence to name names".
A host of Conservative politicians have been named as alleged child abusers on blogs and social media, often without evidence.
"There are lots of accusations flying around on the Internet, lots of names on the Internet. We need to be very careful," Cameron's spokesman told reporters.
"We should not have people just throwing accusations around and trial by Twitter."
Meanwhile, police said they had arrested two men in northern England, including Savile's former housemate Ray Teret, on suspicion of rape, following allegations of sexual abuse many years ago.
Officers in London are looking into claims made by hundreds of victims that Savile and accomplices abused them. They have already questioned former glam rock singer Gary Glitter and comedian Freddie Starr as part of their investigation.
Both men have been released on bail.