Ministers yesterday appeared divided over plans to put animal rights extremists under house arrest.

Home Office Minister Hazel Blears said last week controversial control orders being drawn up to deal with terror suspects could apply to animal activists.

But Trade and Industry Secretary Patricia Hewitt said it was a separate issue.

Asked last week if the control orders could be used against Northern Ireland or animal rights terrorists, Ms Blears said: "Yes. What we are saying is, if there is a serious threat from terrorists who would threaten this country then we should respond to that."

She said animal rights activists could find themselves under house arrest, but Ms Hewitt said that was not the case.

"My understanding is that what we are proposing to do in relation to international terrorism is restricted to international terrorism," she said.

Under measures announced yesterday, animal rights extremists will face five years in prison for targeting research centres.

Companies that deal with the animal research industry, including couriers and cleaners, will also be protected from intimidation.

Police will be given powers to arrest anyone protesting outside scientists' homes.

Powers will also be introduced to ban protestors from the vicinity of someone's house for three months.

The crackdown will be tabled as part of the Serious Organised Crime and Police Bill, which will make it a criminal offence to cause "economic damage" through campaigns of intimidation.