Victims of child abuse may feel too threatened to speak out for fear of being attacked by the media as part of a "sensationalist witch-hunt", a former children's minister has warned.

Tim Loughton, the Conservative MP for East Worthing and Shoreham, said he worried victims would fear being "taken out to dry" by the media in the scramble to name public figures as paedophiles.

"We're forgetting that this whole issue is not about the management of the BBC, it's not about the Leveson inquiry, and it's not about celebrities or politicians. It's about fact that a lot of children have been abused over many years and many of them have never had their stories believed or investigated," Loughton said. "The media has made it into a sensationalist witch-hunt rather than focusing on what are horrific levels abuse over many, many years."

Loughton's comments came after the former Conservative minister David Mellor described Steve Messham, the child abuse victim at the heart of the scandal at the BBC, as "a weirdo". Mellor said on the BBC's Sunday Politics show it was "simply ludicrous" that Newsnight had relied on Messham, who apologised on Friday after mistakenly identifying Lord McAlpine as his attacker at a north Wales care home in the 1970s. Mellor was referring to a Mail on Sunday investigation that raised questions over Messham's credibility as a witness at a trial almost 20 years ago.

Asked about Mellor's comments and the Mail on Sunday report, Loughton said: "It's really unhelpful. If it means that genuine victims who have been bashed into silence for years are now going to think 'Forget it, I'm not going to stick my head above the parapet because I'm going to get taken out to dry by the media' then that's a real downside to what's been happening. That's the tragedy in all of this."

Mellor's comments were described by the former Tory MP Louise Mensch as "utterly abominable and repellent". The NSPCC raised concerns that abuse victims would be put off from coming forward because of fears about not being believed.

Mellor said: "I don't see how Newsnight as a brand can survive this. The thing about McAlpine was that it was so grotesque, they rely on a man who … the Mail on Sunday over two pages reveals that this man is a weirdo.

"He's already cost £1.5m costs when he accused a policeman of sexually abusing him, and why didn't they show a photograph? It's extraordinary.

"The idea of Alastair McAlpine being involved in child abuse is simply ludicrous and someone on Newsnight should have had the sophistication to realise that."

Newsnight's decision to broadcast Messham's mistaken claims led to the resignation of the BBC director general, George Entwistle, who said there had been "unacceptable journalistic standards" at the BBC2 current affairs programme.

John Cameron, the head of child protection operations at the NSPCC, said the child abuse saga was in danger of becoming a trial by media and described Mellor's comments on Messham as unhelpful.

"I'd like anybody who has to make adverse criticism of someone who is saying they have been a victim of abuse to think very carefully about how that is helpful, both to that individual and to those who have been victims of abuse and who will want to come forward," he said.

"There are children out there today who are suffering abuse and people need to reflect very strongly on any commentary about victims and how that could prevent people coming forward."

Mellor's comments on Messham were one of the most discussed topics on Twitter in the UK on Sunday afternoon as people reacted with outrage.

The Sunday Politics presenter Andrew Neil later in the show made clear he did not agree with Mellor's "weirdo" comment.

He said: "I think there's a difference between being unreliable – given what you've gone through – and being described as a weirdo which I don't agree with."

The child protection expert Mark Williams-Thomas, whose ITV Exposure documentary on Jimmy Savile kickstarted the unravelling of a national child abuse scandal, said Mellor's attack on Messham was "appalling". He also criticised the BBC, which he said had not sought to publicly deflect criticism from Messham.

"Steve has been the centre of this recent situation at the BBC, so the BBC, the Bureau of Investigative Journalism and anyone who has had direct contact with him owe it to him to give him proper support and care," Williams-Thomas said. "If that is not happening that is an absolute disgrace. Abuse victims are not pawns in someone else's games."

He said great care needed to be taken when working with abuse victims, some of whom would be attempting to reconstruct traumatic events that happened 30 or 40 years ago. "Great care needs to be taken and ultimately it takes many, many months to tell their story in the right way. This isn't something you can do in five days."

Messham has described how he suffered sexual abuse, including rape, by dozens of attackers at care homes in the 1970s. Earlier on Sunday the former children's minister Tim Loughton urged the public not to forget that this was ultimately a scandal about "horrific" experiences of child abuse.

"Underlying all of this we mustn't forget that vulnerable children, young people, going back many decades have been subject to pretty horrific abuse," he told BBC Radio 4's World at One programme.