Animal rights activists could face five years in prison for targeting research centres under measures to be published by the government.

The plans, part of the Serious Organised Crime and Police Bill, follow attacks on scientists and breeders.

These include graffiti, hate mail, malicious phone calls, hoax bombs and arson attacks.

Government Response: Department of Trade and Industry

Patricia Hewitt, secretary of state for trade and industry, said:  "The simple fact is attacks by animal rights extremists put medical breakthroughs in areas like Aids, cancer and Alzheimer's directly at risk.

"This new law would not affect the important right to peaceful protest, while cracking down hard on those extremists committing crimes - and some horrific acts - against innocent people involved in the supply chain.

"Animal rights extremists pose a real threat to investment in the