Experts on animal rights extremism warned this week that any staff member of a university could be at risk of attack, regardless of their specialism, as activists home in on secondary and tertiary targets.
Last Friday, the Home Office announced a series of "tough" measures to deal with extremists who threaten or physically attack those involved in animal research.
But leading defenders of animal research warned this week that the battle against extremists at Oxford University, which has become the focus of attention because it is building a new £18 million animal research laboratory, was far from over.
Simon Festing, director of public dialogue at the Association of Medical Research Charities, said: "However much money you spend, I don't think you can stop the problems, especially at a university. Why would they want to get into an animal lab only? That isn't how they work. They can target absolutely anything."
Barry Keverne, chair of the Royal Society's committee on animals in research, said: "It is quite clear that the animal liberationists are focusing on weak targets: people who have nothing to do with research."
Professor Keverne's committee has found that cash-strapped universities are spending an average of £175,000 a year on security measures to defend employees against animal extremism. He added that at some universities the bills were stretching into the millions.
Professor Keverne expressed disappointment that last week's announcement from the Home Office, which included police powers to ban protestors from the vicinity of a person's home for three months, did not mention universities. He said: "Industry can raise millions of pounds just to target this, but we simply can't do that."
Last week Bristol University became one of the first universities to take a stand and place a statement about its research using animals on its website.
Oxford University is the only other institution to have gone public in this way, although others are believed to be considering it.