Academics and health campaigners are being subjected to threats of violence, harassment and personal abuse by pro-smoking activists as UK ministers consult over whether tobacco should be sold only in plain packets.

Leading advocates of tobacco control have been targeted in an apparent escalation of hate campaigns and intimidation by bloggers and groups who view moves to curb smoking as assaults on personal freedom.

One article, called "sniper the flappers," hosted by the campaign group Freedom2choose's website in March, suggested shooting staff of Action and Smoking and Health and Cancer Research UK, entrepreneur and anti-smoker Duncan Bannatyne and Shona Robison, a former health minister in the Scottish government. The blogpost gave the addresses of Ash offices in London, Edinburgh and Cardiff. Ash called the police.

"Snipers could soon snuff out prohibitionists ... It is time the humble smoker fought back against this intolerable persecution, for persecution is exactly what it is ... After 'popping' a few termites ASHites, CRUK'ers and a few 'flappers' they might start to take some notice and report the truth," it said.

Freedom2choose, which campaigns "to prevent the victimisation of smokers," removed the article, which it said was satirical. It is still hosted by the website of Smokers Justice, which calls Ash "this new cancer in our society [that] needs to be eradicated."

Researchers say abuse and threats intensified first with the public debate on removing branding from cigarette packs and now a formal government consultation on the idea.

Bath University has increased security for its tobacco control research group, including installing CCTV. Staff were subjected to abusive and threatening phone calls and emails after publishing an article in January about the illegal trade in a smokeless tobacco called snus.

One caller left a message to be passed to Anna Gilmore, the group's director, saying: "Tell her that I know people that would like to meet with her in a dark alley."

The group received about seven calls a day for two months. "The ones I answered were intimidatory; the tone was aggressive. Many of my team felt threatened and worried by this," said Gilmore.

"We've had abuse before, over the debate about banning smoking in public places, and I get some of this every time I publish a paper, but it's increasing...This is part of a deliberate attempt to misinform the public and politicians, denigrate our research and to harass, denigrate and undermine us as researchers."

Bath University has launched a new website, TobaccoTactics.org, to monitor and counter moves by the industry and its supporters to fight control measures. Linda Bauld of Stirling University called the police last September when a pro-smoking blogger calling himself Frank Davis wrote that: "You should start worrying when bricks start getting thrown through your window or messages daubed on your door."

Bauld should emigrate, Davis added, so she would be elsewhere "when your old university department gets torched and your old colleagues are strung up from lamp-posts."

Bauld said she had received threatening phone calls while she and a colleague had also had "not particularly pleasant emails" after publishing a review of plain tobacco packaging which led to the government consultation."A lot of the stuff targeted at me was quite misogynist early on".

Liberal Democrat MP Stephen Williams, chair of Westminster's all party parliamentary group on smoking and health, has received abuse, including homophobic abuse, on his blog, especially after supporting plain packs. "When people make comments online, I sometimes wonder whether it is a real person or manufactured false identity. There are various front groups for the tobacco industry, and , I think, front individuals who post negative comments."

Another prominent plain packs advocate experienced attempts to reset passwords on Hotmail, Facebook and iTunes accounts. Friends and relatives on his Facebook page have been contacted by people asking questions about him.

Davis has said of Ash's director Deborah Arnott that "I'd have had a hard time preventing myself from strangling Arnott on the spot and on camera, or bludgeoning her to death with a microphone stand." He calls anti-smoking campaigners "Nazis" and has compared Arnott, to Hitler.

Arnott said: "I'm happy to argue on the basis of facts and evidence. But when it comes to personal abuse and intimidation, that's completely unacceptable. It does seem to have got worse since plain packs began being debated last year." She believes tobacco industry fears over plain packaging of cigarettes are linked to the apparent upsurge in vitriol and threats, although there is no evidence firms are in any way funding or connected to it.

Another libertarian pro-tobacco blogger, calling himself Dick Puddlecote, wrote that the NHS-funded Smokefree Southwest campaign was made up of "grasping bastards" and called Gabriel Scally, until recently NHS regional director of public health, "part of a bullshit spreading campaign".

Simon Clark, the director of the Freedom Organisation for the Right to Enjoy Smoking (Forest), who called Frank Davis's article "stunning", said he should rather have described it as "powerful".

"We would never condone threats of any kind, nor do we encourage inflammatory language. The blog in question does not represent our views but it is representative of a small and increasingly vocal minority who are angry at the excessive nature of the smoking ban and the never-ending measures designed to denormalise both smokers and their habit."

Clark said that since UK-wide bans on smoking in public places many smokers felt disenfranchised. "It is hardly surprising if their frustration occasionally bubbles over and is expressed in colourful or sometimes inappropriate language."

As for comparisons to Nazis, "As I have said many times, repeated references to a totalitarian regime that slaughtered six million Jews is inappropriate and embarrassing in relation to tobacco control. In terms of building support for our cause, it is entirely counter-productive."

• The caption on the photograph at the top of this article was amended on 11 June 2012 to clarify that brand names would still appear on cigarette packs under new proposals.